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Home >> Mazda >> 1999 >> B2500 SX, Automatic >> Repair and Diagnosis >> External Pages >> Different car >> Section 4 (Engine Controls - Self-Diagnostics - EEC-V - 6.8L (99S E Series & 99S F350 To F550)) >> System Tests >> Test HX: Evaporative Emission (EVAP) Monitor & System >> Diagnostic Aids

Diagnostic Aids

WARNING: This page does not describe the selected car, but rather 26 other vehicles, including the 1999 Mercury Tracer, 1999 Mercury Sable, 1999 Mercury Mystique, 1999 Mercury Mountaineer, and 1999 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.

Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used to diagnose the following:

To identify EVAP system components, see appropriate illustration. See Fig 1-Fig 7 .

Fig 1: Identifying EVAP System Components (Continental, Mustang, Sable & Taurus)
G99A02607Courtesy of FORD MOTOR CO.
Fig 2: Identifying EVAP System Components (Crown Victoria, Grand Marquis & Town Car)
G98C00226Courtesy of FORD MOTOR CO.
Fig 3: Identifying EVAP System Components (Econoline, Expedition, Navigator, Pickup & Ranger; Also Used On Early Model Introduction On Contour, Cougar, Escort ZX2 & Mystique)
G98I00230Courtesy of FORD MOTOR CO.
NOTE: Contour and Mystique use a 3-turn fuel filler cap. All other models use 1/8-turn fuel filler cap.
Fig 4: Identifying EVAP System Components (Escort & Tracer; Also Used On Late Model Introduction On Contour, Cougar, Escort ZX2 & Mystique)
G98B00225Courtesy of FORD MOTOR CO.
Fig 5: Identifying EVAP System Components (Explorer & Mountaineer)
G98D00227Courtesy of FORD MOTOR CO.
Fig 6: Identifying EVAP System Components (Taurus Flex Fuel & Taurus SHO)
G98F00229Courtesy of FORD MOTOR CO.
Fig 7: Identifying EVAP System Components (Windstar)
G98E00228Courtesy of FORD MOTOR CO.
    NOTE: Check for presence of fuel cap. Go to step  2) before tightening a loose cap or checking for a cross threaded cap.

  1. 1) Continuous Memory DTC P0442
    This DTC indicates a fuel vapor leak has been detected. Verify Canister Vent (CV) solenoid is properly seated on EVAP canister (if possible). Visually inspect for cut or loose connector to fuel vapor hoses/tubes in following locations:
    • EVAP canister-to-EVAP canister purge valve.
    • EVAP canister-to-fuel vapor vent valve assembly.
    • Fuel valve control valve tube assembly-to-fuel tank (if applicable).
    • Check for fuel filler pipe damage.

    If no faults are found, go to next step. If any faults are found, repair as necessary. After repair is complete, go to next step.

    2. NOTE: When checking EVAP system for leaks or blockage, energize (close) Canister Vent (CV) solenoid for a maximum of 9 minutes per test step. Then de-energize CV solenoid prior to performing the next test step. This is done to ensure proper closing of CV solenoid.

  2. 2) Check For EVAP System Leaks At Evaporative Emission Test Port
    Disconnect and plug EVAP return tube (EVAP canister purge valve-to-intake manifold) at intake manifold vacuum source. Turn ignition on. Using scan tool, select VPWR PID from PID/DATA monitor menu. If PID voltage is less than 12 volts, go to step  61). If PID voltage is 12 volts or more, locate evaporative test port (marked EVAPORATIVE SERVICE PORT) between EVAP canister purge valve and EVAP canister. If vehicle does not have a test port, go to next step. Install EVAP System Leak Tester (134-00056) including compressed gas source (nitrogen or argon) and pressure regulator to test port. Using scan tool, energize (close) CV solenoid by entering OUTPUT TEST MODE, and turning all outputs on. Select ALL OFF mode and press START button on scan tool. Regulate gas pressure on tester to 14 in. H2 O. Using instructions provided with EVAP system leak tester, pressurize EVAP system. Follow system leak test instructions provided with tester. If pressure stays at more than 8 in. H2 O, disconnect tester and go to next step. If pressure drops to 8 in. H2 O or less, check fuel filler cap for damage. Replace cap as necessary and retest. If fuel filler cap is okay, disconnect tester and go to next step.

  3. 3) Check For Small Leaks At Fuel Filler Cap

    Install EVAP system leak tester to fuel filler pipe. Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Using leak detector provided with test kit, check for leakage at fuel filler cap area and evaporative test port. If no leak is indicated, unable to duplicate fault at this time. If a leak is indicated, replace fuel filler cap or evaporative test port (test port may be part of EVAP canister purge valve) and repeat this step to verify repair. If leak is still indicated, go to next step. If no leak is indicated, testing is complete.

  4. 4) Leak Test System With Tester At Fill Position

    Connect EVAP system leak tester to evaporative test port. Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Select ALL OFF mode and push START button. Regulate gas pressure on tester to 14 in. H2 O. Follow system leak test instructions provided with tester. Turn selector on tester to FILL position. Pressurize EVAP system to 14 in. H2 O. If pressure stays at 13.8-14.2 in. H2 O, go to next step. If pressure drops to less than 13.8 in. H2 O, discontinue pressurizing EVAP system and go to step  6).
    5. NOTE: To ensure CV solenoid remains closed, DO NOT energize solenoid with scan tool for more than 9 minutes. If necessary, de-energize CV solenoid with some time passing then re-energize solenoid.

  5. 5) Check Complete EVAP System
    Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Using leak detector provided with test kit, check for leakage between the following EVAP system locations:
    • Check EVAP return tube-to-EVAP canister purge valve.
    • Check EVAP canister purge valve-to-EVAP CV solenoid.
    • Check EVAP canister-to-fuel tank.
    • Check fuel filler pipe and fuel cap.

    If leak is detected, repair as necessary. After repair is complete, go to next step. If no leak is detected, discontinue pressurizing EVAP system and go to next step.

    6. NOTE: Mustang, Ranger, Town Car and Windstar have a quick disconnect between the EVAP canister tube and front fuel vapor hose assembly (fuel tank-to-EVAP canister). This quick disconnect is used as an alternative location to a fuel vapor tee or "F" fitting on the EVAP canister for leak check purposes.

  6. 6) Check For Leak Between EVAP Return Tube & EVAP Canister
    Turn ignition off. Disconnect EVAP canister tube (from fuel tank) at fuel vapor tee located between EVAP canister purge valve and EVAP canister (or "F" fitting on EVAP canister). Plug or cap fuel vapor tee (or fitting on canister). Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Using leak detector provided with test kit, check for leakage at the following EVAP system locations:
    • Check EVAP return tube (intake manifold-to-EVAP canister purge valve).
    • Check EVAP canister purge outlet tube (EVAP canister purge valve-to-EVAP canister CV solenoid assembly.
    • Check EVAP canister vent hose.

    If no leak is indicated, remove plug or cap from fuel vapor tee (or fitting on canister). Go to next step. If a leak is indicated, repair as necessary and repeat this step to verify repair. Go to next step.

  7. 7) Check For Leak Between EVAP Canister Tube & Fuel Tank

    Turn ignition off. Remove EVAP system leak tester. Remove fuel filler cap. Install EVAP system leak tester to fuel filler pipe. Plug open end of EVAP canister tube (from fuel tank) at fuel vapor tee (or fitting on canister). Turn ignition on. Turn selector on tester to FILL position. Pressurize EVAP system to 14 in. H2 O. Using leak detector provided with test kit, check for leakage at EVAP canister tube between fuel tank and EVAP canister. Also check for leakage at fuel tank pressure sensor, fuel vapor vent valve(s) fuel vapor control valve and fuel filler pipe. If no leak is indicated, go to next step. If a leak is indicated, repair as necessary. Repeat this step to verify repair then go to next step.

  8. 8) Verification Leak Check At Fuel Filler Pipe

    Turn ignition off. Reconnect EVAP canister tube to fuel vapor tee (or fitting on canister) Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Follow instructions provided with EVAP system leak tester and perform system leak test. If no leak is indicated, no fault is indicated at this time. Testing is complete. If a leak is indicated, return to step  4). Repair as necessary and repeat this step to verify repair.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 8) to step 10). No test procedures have been omitted.

  9. 10) Continuous Memory DTC P0443

    This DTC indicates an intermittent EVAP canister purge valve circuit fault. Repeat KOEO ON-DEMAND SELF-TEST  and KOER ON-DEMAND SELF-TEST. If DTC P0443 is present in Continuous Memory only, check for intermittent fault. Go to TEST Z . If no fault is indicated after performing TEST Z, replace PCM. If DTC P0443 is present in KOEO or KOER self-test, go to next step.

  10. 11) DTC P0443: Check VPWR Circuit Voltage

    Turn ignition off. Disconnect EVAP canister purge valve connector. Turn ignition on. Measure voltage between VPWR terminal at EVAP canister purge valve wiring harness connector and negative battery terminal. See Fig 8. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less, repair open in VPWR circuit.
    Fig 8: Identifying EVAP Canister Purge Valve Circuits & Connector Terminals
    G99A02612Courtesy of FORD MOTOR CO.

  11. 12) Check EVAP Canister Purge Valve Resistance

    To check EVAP CANP valve resistance, engine must be cold. Turn ignition off. Measure resistance between EVAP canister purge valve terminals. If resistance is 30-38 ohms, go to next step. If resistance is not 30-38 ohms, replace EVAP canister purge valve.

  12. 13) Check EVAP Canister Purge Valve Circuit Resistance

    Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Measure resistance between PCM connector pin No. 56 and EVAP CANISTER PURGE terminal at EVAP canister purge valve wiring harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in EVAP CANISTER PURGE circuit.

  13. 14) Check For Short To Ground

    Disconnect scan tool from DLC. Measure resistance between PCM connector pin No. 56 and negative battery terminal. If resistance is 10,000 ohms or less, repair short to ground in EVAP CANISTER PURGE circuit. If resistance is more than 10,000 ohms, go to next step.

  14. 15) Check Circuit For Short To VPWR

    Turn ignition on. Measure voltage between PCM connector pin No. 56 and negative battery terminal. If any voltage reading is more than 10.5 volts, repair short to VPWR in EVAP CANP PURGE circuit. If both voltage readings are 10.5 volts or less, replace PCM.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 15) to step 18). No test procedures have been omitted.

  15. 18) Continuous Memory DTC P1450

    This DTC indicates that PCM has detected EVAP control system has excessive fuel tank vacuum. Possible causes are:
    • EVAP canister purge tube blocked or kinked.
    • Fuel vapor elbow on EVAP canister is contaminated.
    • Restricted EVAP canister.
    • Canister Vent (CV) solenoid stuck closed.
    • Plugged or contaminated CV solenoid filter.
    • EVAP canister purge valve stuck open.
    • Fuel filler cap stuck closed (no vacuum relief).
    • Open in VREF circuit.
    • Faulty Fuel Tank Pressure (FTP) sensor.

    Check for kinks in fuel vapor hoses/tubes. Visually inspect EVAP canister inlet port, CV solenoid filter and canister vent hose for contamination or debris. Check CV solenoid filter for blockage or contamination. Repair as necessary and go to next step. If no faults are found, go to next step.

  16. 19) Check For Blockage

    Disconnect and plug EVAP return tube (EVAP canister purge valve-to-intake manifold) at intake manifold vacuum source. Plug CV solenoid (or filter) or plug canister vent hose. Locate evaporative test port (marked EVAPORATIVE SERVICE PORT) between EVAP canister purge valve and EVAP canister. Install EVAP System Leak Tester (134-00056) including compressed gas source (nitrogen or argon) and pressure regulator to test port. Regulate gas pressure on tester to 14 in. H2 O. Using instructions provided with EVAP system leak tester, pressurize EVAP system. Remove plug from CV solenoid (or filter) or from canister vent hose. If pressure drops rapidly, remove EVAP system leak tester and go to next step. If pressure does not drop rapidly, blockage exists. Check the following:
    • Check for faulty vent solenoid.
    • Check for faulty or plugged EVAP canister.
    • Check for kinked, plugged or damaged EVAP hoses/tubes.

    Repair as necessary and repeat this step to verify repair. Go to step  22).

    17. NOTE: When checking EVAP system for leaks or blockage, energize (close) Canister Vent (CV) solenoid for a maximum of 9 minutes per test step. Then de-energize CV solenoid prior to performing the next test step. This is done to ensure proper closing of CV solenoid.

  17. 20) Pressure Check Fuel Filler Cap
    Install EVAP system leak tester to fuel filler pipe. Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Using leak detector provided with test kit, check for leakage at fuel filler cap area and evaporative test port. If no leak is indicated, go to next step. If a leak is indicated, replace fuel filler cap or evaporative test port (test port may be part of EVAP canister purge valve) and repeat this step to verify repair. Go to next step.

  18. 21) Check For Blockage With Fuel Filler Cap Removed

    Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Remove fuel filler cap. If pressure drops rapidly, remove EVAP system leak tester and go to next step. If pressure does not drop rapidly, blockage exists. Check the following:
    • Check for faulty vent solenoid.
    • Check for faulty or plugged EVAP canister.
    • Check for kinked, plugged or damaged EVAP hoses/tubes.

    Repair as necessary and repeat this step to verify repair then go to next step.

  19. 22) Check Fuel Tank Pressure Sensor Parameter Identification (PID)

    Remove fuel filler cap. Turn ignition on. Using scan tool, select FTP V PID. If PID voltage is 2.4-2.8 volts, install fuel filler cap and go to next step. If PID voltage is not 2.4-2.8 volts, go to step  24).

  20. 23) Check For Stuck Open EVAP Canister Purge Valve

    Turn ignition off. Remove plug from CV solenoid (or filter) or from plug canister vent hose (if not done previously). Remove plug and reconnect EVAP return tube (EVAP canister purge valve-to-intake manifold) at intake manifold vacuum source. Ensure fuel filler cap is installed. Turn ignition on. Using scan tool, select FTP V and EVAPPDC PIDs. Start engine. When EVAPPDC PID reading is zero, if FTP V PID voltage is less than 2.4 volts, EVAP canister purge valve is stuck open. Replace EVAP canister purge valve. When EVAPPDC PID reading is zero, if FTP V PID voltage is 2.4 volts or more, blockage still exists in EVAP system between evaporative test port and fuel tank or between EVAP canister and CV solenoid. Repair as necessary or return to step  19) to help determine blockage location.

  21. 24) Check Voltage Between VREF & SIG RTN Circuits

    Turn ignition off. Disconnect FTP sensor connector, located on top of fuel tank. Turn ignition on. Measure voltage between VREF and SIG RTN terminals at FTP sensor wiring harness connector. See Fig 9. If voltage is 4-6 volts, replace FTP sensor. If voltage is not 4-6 volts, go to next step.
    Fig 9: Identifying FTP Sensor Circuits & Connector Terminals
    G99E02614Courtesy of FORD MOTOR CO.

  22. 25) Check For Open VREF Circuit

    Turn ignition off. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Measure resistance between PCM connector pin No. 90 and VREF terminal at FTP sensor wiring harness connector. If resistance is less than 5 ohms, replace PCM. Go to step  22) to verify repair. If resistance is 5 ohms or more, repair open in VREF circuit. Go to step  22) to verify repair.

  23. 26) DTC P0452: Check FTP Sensor Connector

    This DTC indicates FTP circuit input is below minimum. Turn ignition off. Visually inspect FTP sensor connector for liquid fuel contamination. FTP sensor is located on top of fuel tank. Repair as necessary. If connector is okay, go to next step.

  24. 27) Check FTP Sensor Voltage

    Turn ignition on. Using scan tool, select FTP V PID. If FTP V PID is not available on scan tool, measure voltage between PCM connector pins No. 62 (FTP) and No. 91 (SIG RTN). If measure voltage or PID voltage is less than .22 volt, go to next step. If voltage is .22 volt or more, fault is intermittent. Go to TEST Z .

  25. 28) Check Opposite Induced High FTP Signal

    Turn ignition off. Disconnect FTP sensor connector. Connect a jumper wire between VREF and FTP terminals at FTP sensor wiring harness connector. Turn ignition on. If scan tool communication link error is displayed, remove jumper wire and go to next step. Using scan tool, select FTP V PID. If FTP V PID is not available on scan tool, measure voltage between PCM connector pins No. 62 (FTP) and No. 91 (SIG RTN). If measured voltage or PID voltage is not 4-6 volts, remove jumper wire and go to next step. If voltage is 4-6 volts, replace FTP sensor.

  26. 29) Check Voltage At FTP Sensor Connector

    Measure voltage between VREF and SIG RTN terminals at FTP sensor wiring harness connector. See Fig 9. If voltage is 4-6 volts, go to next step. If voltage is not 4-6 volts, VREF voltage is out of range. Go to TEST C .

  27. 30) Check For Short Circuit

    Turn ignition off. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Disconnect scan tool from DLC. Measure resistance between PCM connector pins No. 62 and 103. Also measure resistance between PCM connector pin No. 62 and negative battery terminal. If both resistance readings are more than 10,000 ohms, replace PCM. If any resistance reading is 10,000 ohms or less, repair FTP circuit short to SIG RTN or PWR GND circuit.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 30) to step 33). No test procedures have been omitted.

  28. 33) DTC P0453: Check FTP Sensor Voltage

    Turn ignition on. Using scan tool, select FTP V PID. If FTP V PID is not available on scan tool, measure voltage between PCM connector pins No. 62 (FTP) and No. 91 (SIG RTN). If measured voltage or PID voltage is more than 4.5 volts, go to next step. If voltage is 4.5 volts or less, fault is intermittent. Go to TEST Z .

  29. 34) Check For Short To Power

    Turn ignition off. Disconnect FTP sensor connector, located on top of fuel tank. Turn ignition on. Measure voltage between FTP terminal at FTP sensor wiring harness connector and negative battery terminal. See Fig 9. If voltage is 10.5 volts or less, go to step  36). If voltage is more than 10.5 volts, a short to VPWR exists. Go to next step.

  30. 35) Check FTP Circuit For Short To VPWR Circuit

    Turn ignition off. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Turn ignition on. Measure voltage between PCM connector pin No. 62 and negative battery terminal. If voltage is more than 10.5 volts, repair short circuit. If voltage is 10.5 volts or less, replace PCM.

  31. 36) Check Opposite Induced Low FTP Signal

    Turn ignition off. Connect a jumper wire between SIG RTN and FTP terminals at FTP sensor wiring harness connector. Turn ignition on. If scan tool communication link error is displayed, remove jumper wire and go to step  41). Using scan tool, select FTP V PID. If FTP V PID is not available on scan tool, measure voltage between PCM connector pins No. 62 (FTP) and No. 91 (SIG RTN). If PID voltage is less than .1 volt, remove jumper wire and go to next step. If PID voltage is .1 volt or more, unable to induce opposite signal. Go to step  39).

  32. 37) Check Voltage At FTP Sensor Connector

    Ensure ignition is on. Measure voltage between VREF and SIG RTN terminals at FTP sensor wiring harness connector. If voltage is 4-6 volts, go to next step. If voltage is not 4-6 volts, VREF voltage is out of range. Go to TEST C .

  33. 38) Check For Short Circuit

    Turn ignition off. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Measure resistance between PCM connector pins No. 62 and 90. If resistance is more than 10,000 ohms, replace FTP sensor. If resistance is 10,000 ohms or less, repair FTP circuit short to VREF circuit.

  34. 39) Check For Open FTP Circuit

    Turn ignition off. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Measure resistance between PCM connector pin No. 62 and FTP terminal at FTP sensor wiring harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in FTP circuit.

  35. 40) Check For Open SIG RTN Circuit

    Measure resistance between PCM connector pin No. 91 and SIG RTN terminal at FTP sensor wiring harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in SIG RTN circuit.

  36. 41) Check FTP Circuit For Short To VREF Circuit

    Measure resistance between PCM connector pins No. 62 and 90. If resistance is more than 10,000 ohms, replace PCM. If resistance is 10,000 ohms or less, repair FTP circuit short to VREF circuit.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 41) to step 44). No test procedures have been omitted.

  37. 43) DTC P0457: Check For Missing Or Leaking Fuel Filler Cap

    This DTC is set when PCM detects a fuel tank pressure decreases more than 7 in. H2 O within 30 seconds after refueling, or excessive purge (fuel vapor) flow more than .06 lbs. per minute. Possible causes are:
    • Fuel Filler Cap Not Installed After Refueling (CHECK FUEL CAP Indicator May Be Illuminated)
    • Fuel Filler Cap Loose Or Cross-Threaded

    Check for missing, cross-threaded or leaking fuel filler cap. Repair or replace as necessary. Clear DTCs. Perform DRIVE CYCLES  under ADDITIONAL SYSTEM FUNCTIONS. Ensure OBD-II DRIVE CYCLE PROCEDURES are performed to verify repair. After drive cycle is complete, repeat QUICK TEST . If DTC P0455 or P0457 is present, see EVAPORATIVE EMISSIONS SYMPTOMS  table under SYSTEM TESTS (EVAPORATIVE EMISSIONS). If a missing, cross-threaded or leaking fuel filler cap condition was not found, clear DTCs. Perform DRIVE CYCLES  under ADDITIONAL SYSTEM FUNCTIONS. Ensure OBD-II DRIVE CYCLE PROCEDURES are performed to verify repair. After drive cycle is complete, repeat QUICK TEST . If DTC P0455 is present, see EVAPORATIVE EMISSIONS SYMPTOMS  table.

  38. 44) Continuous Memory DTC P0455

    This DTC indicates a large fuel vapor leak or no purge flow has been detected. Check the following for possible cause for this fault:
    • Faulty aftermarket EVAP system components.
    • Faulty fuel filler cap.
    • Faulty fuel vapor hoses or tubes.
    • Faulty EVAP system components.
    • CV solenoid partially stuck open.
    • Faulty Fuel Tank Pressure (FTP) sensor.
    • Faulty EVAP canister.

    If no faults are found, go to next step. If any faults are found, repair as necessary. After repair is complete, go to next step.

    39. NOTE: When checking EVAP system for leaks or blockage, energize (close) Canister Vent (CV) solenoid for a maximum of 9 minutes per test step. Then de-energize CV solenoid prior to performing the next test step. This is done to ensure proper closing of CV solenoid.

  39. 45) Check For EVAP System Leaks
    Disconnect and plug EVAP return tube (EVAP canister purge valve-to-intake manifold) at intake manifold vacuum source. Turn ignition on. Using scan tool, select VPWR PID from PID/DATA monitor menu. If PID voltage is less than 12 volts, go to step  61). If PID voltage is 12 volts or more, locate evaporative test port (marked EVAPORATIVE SERVICE PORT) between EVAP canister purge valve and EVAP canister. If vehicle does not have a test port, go to step  50). Install EVAP System Leak Tester (134-00056) including compressed gas source (nitrogen or argon) and pressure regulator to test port. Using scan tool, energize CV solenoid by entering OUTPUT TEST MODE, and turning all outputs on. Select ALL OFF mode and press START button on scan tool. Regulate gas pressure on tester to 14 in. H2 O. Using instructions provided with EVAP system leak tester, pressurize EVAP system. Follow system leak test instructions provided with tester. If pressure stays at more than 8 in. H2 O, go to next step. If pressure drops to 8 in. H2 O or less, remove EVAP system leak tester and go to step  50).

  40. 46) Check For Blockage

    Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Command all outputs OFF. If pressure drops rapidly, go to step  48). If pressure does not drop rapidly, go to next step.

  41. 47) Check For Blockage Between EVAP Canister Purge Valve & EVAP Canister

    Disconnect and plug EVAP canister purge outlet tube (between EVAP canister purge valve and EVAP canister) at EVAP canister. Re-pressurize system to 14 in. H2 O. Remove plug from outlet tube. If system does not immediately lose pressure, remove blockage or contamination from EVAP canister purge outlet tube, or replace tube. Go to step  46) to verify repair. If system immediately releases pressure, check the following:
    • Check for faulty vent solenoid.
    • Check for faulty or plugged EVAP canister.
    • Check for kinked, plugged or damaged EVAP hoses/tubes.

    Repair as necessary. Repeat test step  46) to verify repair and go to next step.

  42. 48) Check For Blockage Between EVAP Test Port & Fuel Tank

    Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Remove fuel filler cap. If pressure drops to zero, leave fuel filler cap off and go to step  56). If pressure does not drop to zero, remove EVAP system leak tester and go to next step.

  43. 49) Check For Blockage Between Fuel Tank & EVAP Canister Tube

    Install EVAP system leak tester at fuel filler pipe. Disconnect and plug EVAP canister tube (from fuel tank) at fuel vapor tee located between EVAP canister purge valve and EVAP canister (or "F" fitting on canister). Turn ignition on. Pressurize EVAP system to 14 in. H2 O. Remove plug from EVAP canister tube. If pressure drops, install fuel filler cap, EVAP canister tube and go to step  56). If pressure does not drop, check the following:
    • Check for faulty vent solenoid.
    • Check for faulty or plugged EVAP canister.
    • Check for kinked, plugged or damaged EVAP hoses/tubes.

    Repair as necessary. Repeat step  48) to verify repair. Leave fuel filler cap off and go to step  56).

  44. 50) Check For Leaks At Fuel Filler Cap Area

    Install EVAP system leak tester to fuel filler pipe. Using scan tool, energize CV solenoid by entering OUTPUT TEST MODE, and turning all outputs on. Pressurize EVAP system to 14 in. H2 O. Follow system leak test instructions provided with tester and check for leaks around fuel filler cap. If no leak is detected, remove EVAP system leak tester and install fuel filler cap. Go to next step. If a leak is detected, replace fuel filler cap and repeat this step to verify repair. If leak is still indicated, go to next step. If no leak is indicated, testing is complete.

  45. 51) Check EVAP Canister

    Plug CV solenoid (or filter) or plug canister vent hose. Locate evaporative test port (marked EVAPORATIVE SERVICE PORT) between EVAP canister purge valve and EVAP canister and install EVAP system leak tester. Pressurize EVAP system to 14 in. H2 O. Using leak detector provided with test kit, check for leakage at EVAP canister and CV solenoid assembly. If no leak is indicated, go to next step. If a leak is indicated, repair as necessary. Repeat step  45) to verify repair. If leak is still indicated, go to next step. If no leak is indicated, testing is complete.

  46. 52) Check For Leak Between EVAP Test Port & EVAP Canister

    Disconnect EVAP canister tube (from fuel tank) at fuel vapor tee located between EVAP canister purge valve and EVAP canister (or "F" fitting on canister). Plug or cap fuel vapor tee (or fitting on canister). Turn ignition on. Using scan tool, access OUTPUT TEST MODE. Turn all outputs on. Pressurize EVAP system to 14 in. H2 O. Using leak detector provided with test kit, check for leakage at EVAP return tube between intake manifold source and EVAP canister. If leak is detected, repair as necessary. After repair is complete, reconnect all components and go to next step. If no leak is detected, go to step  54).

  47. 53) Verify Repair

    Disconnect and plug EVAP return tube (EVAP canister purge valve-to-intake manifold) at intake manifold vacuum source. Locate evaporative test port (marked EVAPORATIVE SERVICE PORT) between EVAP canister purge valve and EVAP canister. Install EVAP system leak tester to test port. Using scan tool, energize CV solenoid by entering OUTPUT TEST MODE, and turning all outputs on. Select ALL OFF mode and press START button on scan tool. Regulate gas pressure on tester to 14 in. H2 O. Using instructions provided with EVAP system leak tester, pressurize EVAP system. If pressure stays at more than 8 in. H2 O remove EVAP system leak tester. Leave fuel filler cap off and go to step  56). If pressure drops to 8 in. H2 O or less, remove EVAP system leak tester and go to next step.
    48. NOTE: Mustang, Ranger, Town Car and Windstar have a quick disconnect between the EVAP canister tube and front fuel vapor hose assembly (fuel tank-to-EVAP canister). This quick disconnect is used as an alternative location to a fuel vapor tee or "F" fitting on the EVAP canister for leak check purposes.

  48. 54) Check For Leak Between EVAP Canister Tube & Fuel Tank
    Turn ignition off. Disconnect EVAP canister tube (from fuel tank) at fuel vapor tee located between EVAP canister purge valve and EVAP canister (or "F" fitting on canister). Plug or cap fuel vapor tee (or fitting on canister). Install EVAP system leak tester to fuel filler pipe. Pressurize EVAP system to 14 in. H2 O. Using leak detector provided with test kit, check for leakage at the following components:
    • Fuel filler pipe.
    • Fuel tank.
    • Fuel vapor control valve tube assembly.
    • FTP sensor.
    • EVAP canister tube between fuel vapor control valve and EVAP canister.

    Repair as necessary. After repair is complete, go to next step to verify repair. If no leak is detected, remove plug from EVAP canister tube. Reconnect EVAP canister tube and install fuel filler cap. Remove EVAP system leak tester from fuel filler pipe and install at EVAP test port. Perform step  53) to verify leak no longer exists. After test is complete, remove fuel filler cap and go to step  56).

  49. 55) Verify Repair

    Pressurize EVAP system to 14 in. H2 O. If pressure drops to 8 in. H2 O or less, leak in EVAP system still exists. Repeat step  54) to isolate leak and repair as necessary. If pressure stays at more than 8 in. H2 O, remove plug from EVAP canister tube and reconnect tube. Install fuel filler cap. Remove EVAP system leak tester from fuel filler pipe and install at EVAP test port. Perform step  53) to verify leak no longer exists. After test is complete, remove fuel filler cap and go to next step.

  50. 56) Check FTP Sensor Operation

    Turn ignition on. Using scan tool, select VPWR PID. If PID voltage is 10.5 volts or less, go to step  61). After completing step, return to this test step and continue testing. If PID voltage is more than 10.5 volts, select FTP V PID. If PID voltage is 2.4-2.8 volts, go to next step. If PID voltage is not 2.4-2.8 volts, replace FTP sensor. Repeat this step to verify repair, then go to next step.

  51. 57) FTP Sensor Functional Check

    Install EVAP leak tester to fuel filler pipe. Plug canister vent hose or close CV solenoid to atmosphere by taping CV filter shut. Turn ignition on. Using scan tool, select FTP V PID. Pressurize EVAP system to 14 in. H2 O. If PID voltage is 4.2-4.9 volts, remove EVAP system leak tester. Remove plug from vent hose or remove tape from CV solenoid filter. Install fuel filler cap and go to next step. If PID voltage is not 4.2-4.9 volts, replace FTP sensor. Repeat step  56) to verify repair.

  52. 58) Check EVAP Canister Purge Valve Operation

    Turn ignition off. Remove plug and connect EVAP return tube at intake manifold vacuum source. Turn ignition on. Using scan tool, select EVAPPDC and FTP V PIDs. Start engine and observe EVAPPDC PID value. Idle engine until EVAPPD PID reaches 40 percent duty cycle. If FTP V PID voltage is less than 2.6 volts, no problem is indicated at this time. Testing is complete. If FTP V PID voltage is 2.6 volts or more, go to next step.
    53. NOTE: At high altitude, the intake manifold vacuum source readings at both the input port vacuum hose and EVAP return tube must be at least 10 in. Hg.
    Fig 10: Identifying EVAP Canister Purge Valve (Escort ZX2, Mustang, Sable & Taurus)
    G99E02609Courtesy of FORD MOTOR CO.
    Fig 11: Identifying EVAP Canister Purge Valve (All Other Models)
    G96C01029Courtesy of FORD MOTOR CO.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 59) to step 61). No test procedures have been omitted.

  53. 59) Check Intake Manifold Vacuum To EVAP Canister Purge Valve
    Turn ignition off. Disconnect input port vacuum hose and EVAP return tube at EVAP canister purge valve. See Fig 10 or Fig 11 . Install vacuum gauge to open end of input port vacuum hose and plug open end of EVAP return tube. Start engine. Note vacuum gauge reading. Turn ignition off. Install vacuum gauge to EVAP return tube and plug open end of input port vacuum hose. Start engine and note vacuum gauge reading. If both vacuum readings are 14-20 in. Hg, replace EVAP canister purge valve. If both vacuum gauge readings are not 14-20 in. Hg, check for blockage in input port vacuum hose or EVAP return tube. Check intake manifold vacuum tree or port for blockage. Repair as necessary. Repeat step  58) to verify repair.

  54. 61) Check Battery Voltage

    Turn ignition off. Measure voltage across battery terminals. If voltage is 12 volts or more, return to step that directed you here and continue EVAP system leak test. If voltage is less than 12 volts, recharge battery and return to step that directed you here and continue EVAP system leak test.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 61) to step 65). No test procedures have been omitted.

  55. 65) DTC P1451: Check Voltage To Canister Vent (CV) Solenoid

    This DTC indicates an CV solenoid circuit fault. Possible causes are:
    • Open VPWR circuit.
    • Open or shorted CV circuit.
    • Faulty CV solenoid.
    • Faulty PCM.

    Turn ignition off. Disconnect CV solenoid connector. Turn ignition on. Measure voltage between VPWR terminal at CV solenoid wiring harness connector and negative battery terminal. See Fig 12. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less, repair open in VPWR circuit.

    Fig 12: Identifying CV Solenoid Circuits & Connector Terminals
    G99J02616Courtesy of FORD MOTOR CO.

  56. 66) Check CV Solenoid Resistance

    Turn ignition off. Measure resistance between CV solenoid terminals. If resistance is 48-65 ohms, go to next step. If resistance is not 48-65 ohms, replace CV solenoid.

  57. 67) Check VPWR Circuit Resistance

    Measure resistance of VPWR circuit between VPWR terminal at CV solenoid wiring harness connector and power relay in fuse/relay junction box. Junction box is located in left side of engine compartment. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in VREF circuit.

  58. 68) Check For Open VPWR Circuit

    Disconnect PCM connector. Measure resistance of VPWR circuit between PCM connector pin No. 71 and CV solenoid wiring harness connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in VPWR circuit.

  59. 69) Check CV Circuit Resistance

    Measure resistance of CV circuit between PCM connector pin No. 67 (Sable and Taurus pin No. 45) and CV terminal at CV solenoid wiring harness connector. If resistance is less than 5 ohms, replace PCM. If resistance is 5 ohms or more, repair open in CV circuit.

  60. 70) Check CV Circuit For Short To Ground

    Turn ignition off. Disconnect PCM connector. Measure resistance between CV terminal at CV solenoid wiring harness connector and negative battery terminal. If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 ohms or less, repair short to ground in CV circuit.

  61. 71) Check CV Circuit Short To PWR Or Chassis Ground

    Turn ignition on. Measure voltage between chassis ground and PCM connector pin No. 67 (Sable and Taurus pin No. 45). If voltage is less than one volt, go to next step. If voltage is one volt or more, repair CV circuit short to VREF, VPWR or chassis ground.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 71) to step 76). No test procedures have been omitted.

  62. 76) DTC P0460: Check Fuel Tank Level

    This DTC indicates a Fuel Level Input (FLI) circuit fault. Possible causes are:
    • Empty fuel tank.
    • Overfilled fuel tank.
    • Faulty fuel pump.
    • Faulty fuel gauge or instrument cluster.
    • FLI circuit fault.
    • CASE GND circuit shorted to VPWR.
    • Faulty PCM.

    On Expedition, Mustang, Navigator, Pickup F150 and Pickup - 5.4L Lightning, Town Car and Windstar, diagnose fuel level indicator or Rear Electronic Module (REM). See appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT in appropriate lemon-25® manual. On all other models, turn ignition on. Note fuel gauge reading. Using scan tool, select FLI PID. If both fuel gauge and FLI PID readings are between 1/4 (30 percent for FLI PID) and 3/4 (70 percent for FLI PID), go to step  78). If readings are not as specified, check fuel tank for leaks. Repair as necessary. If fuel tank is okay, check for faulty fuse for fuel pump-to-fuel gauge circuit. Proceed as follows:

    • If DTC P0460 is present, go to next step.
    • If fuse is blown and DTC P0460 is not present, check for short in VPWR circuit. On Escort, Mustang and Tracer, go to TEST X . On all other models, go to TEST B .
    • If fuel gauge is inoperative and DTC P0460 is not present, go to appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT in appropriate lemon-25® manual and diagnose fuel gauge.

  63. 77) Check For Low Fuel Flow

    Turn ignition on. While observing both fuel gauge and FLI PID, add 2-3 gallons of fuel to fuel tank. If fuel gauge or FLI PID reading does not increase, go to step  79). If either fuel gauge or FLI PID reading increases as fuel is added, drain or fill fuel tank so fuel level is 30-70 percent full. Clear DTCs. Road test vehicle and repeat QUICK TEST . If DTC P0460 is still present, go to next step.

  64. 78) Check FLI Voltage

    Start engine. On Contour, Cougar and Mystique, measure voltage between PCM connector pins No. 12 (FLI) and 91 (SIG RTN). If voltage is 4.39-6.14 volts, go to step  86). If voltage is not 4.39-6.14 volts, go to next step. On all other models, using scan tool, select FLI V PID. If PID voltage is not 1.23-2.25 volts, go to next step. If PID voltage is 1.23-2.25 volts, go to step  87) (Continental) or go to step  86) (all other models).

  65. 79) Check Fuel Pump Module Resistance

    Turn ignition off. Disconnect fuel pump module connector. Measure resistance between FLI and CASE GND terminals at fuel pump module wiring harness connector. See Fig 13-Fig 19 . If resistance is 15-160 ohms, go to next step. If resistance is not 15-160 ohms, check for stuck fuel level float on fuel pump. Repair as necessary. If float moves freely, replace fuel pump module.
    Fig 13: Identifying Fuel Pump Module Circuits & Connector Terminals (Contour, Cougar & Mystique)
    G99C02613Courtesy of FORD MOTOR CO.
    Fig 14: Identifying Fuel Pump Module Circuits & Connector Terminals (Escort & Tracer)
    G99B02622Courtesy of FORD MOTOR CO.
    Fig 15: Identifying Fuel Pump Module Circuits & Connector Terminals (Econoline, Expedition, Navigator & "F" Super-Duty Models)
    G99H02620Courtesy of FORD MOTOR CO.
    Fig 16: Identifying Fuel Pump Module Circuits & Connector Terminals (Continental, Crown Victoria, Explorer, Grand Marquis, Mountaineer, Town Car & Windstar)
    G99D02618Courtesy of FORD MOTOR CO.
    Fig 17: Identifying Fuel Pump Module Circuits & Connector Terminals (Ranger Flex Fuel)
    G99H02615Courtesy of FORD MOTOR CO.
    Fig 18: Identifying Fuel Pump Module Circuits & Connector Terminals (Ranger Gasoline)
    G99B02617Courtesy of FORD MOTOR CO.
    Fig 19: Identifying Fuel Pump Module Circuits & Connector Terminals (Sable & Taurus)
    G99F02619Courtesy of FORD MOTOR CO.

  66. 80) Check FLI Voltage At Fuel Pump Module

    Reconnect all connectors. Disconnect instrument cluster connector to fuel gauge. See appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT in appropriate lemon-25® manual. Start engine and allow to idle. Measure voltage between FLI terminal at fuel pump module wiring harness connector and negative battery terminal. If voltage is more than 5 volts, go to next step. If voltage is 5 volts or less, go to step  82).

  67. 81) Check FLI Circuit For Short To VPWR

    Turn ignition off. Disconnect PCM connector. Measure voltage between FLI terminal at fuel pump module wiring harness connector and negative battery terminal. If voltage is more than 10.5 volts, repair short in FLI circuit. If voltage is not more than 10.5 volts, replace PCM.

  68. 82) Check FLI Circuit For Short To Ground

    Ensure ignition is off. Disconnect PCM connector. Measure resistance between PCM connector pin No. 12 (FLI) or No. 9 (FLI) and negative battery terminal. See Fig 13-Fig 19 . If resistance is more than 10,000 ohms, go to step  84) (Continental) or go to next step (all other models). If resistance is 10,000 ohms or less, repair short to ground.

  69. 83) Check FLI & CASE GND Circuits

    Measure resistance between PCM connector pin No. 25 (CASE GND) and pin No. 12 (FLI) or No. 9 (FLI). If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 ohms or less, repair short between FLI and CASE GND circuits.

  70. 84) Check FLI Circuit For Short To CASE GND (Continental Only)

    Locate virtual image instrument cluster Gray 20-pin connector (C256) and 16-pin connector (C255). See Fig 20. Measure resistance between terminals No. 4 at connector C256 and terminal No. 28 at connector C255. Also measure resistance between terminals No. 4 at connector C256 and terminal No. 27 at connector C255. If both resistance readings are more than 10,000 ohms, go to next step. If any resistance reading is 10,000 ohms or less, repair short between FLI and FUEL LEVEL RETURN circuits or FLI and FUEL LOGIC GROUND circuits
    Fig 20: Identifying Virtual Image Instrument Cluster Wiring Harness Connector Terminals (Continental)
    G97C28607Courtesy of FORD MOTOR CO.

  71. 85) Check For Open In FLI Circuit

    Measure resistance between PCM connector pin No. 12 (FLI) or No. 9 (FLI) and FLI terminal at fuel pump module wiring harness connector. See Fig 13-Fig 19 . Also measure resistance between PCM connector pin No. 12 (FLI) or No. 9 (FLI) and FLI terminal at instrument cluster connector. For instrument cluster connector identification, see appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT in appropriate lemon-25® manual. If both resistance readings are less than 10 ohms, go to step  87) (Continental) or go to next step (all other models). If any resistance reading is 10 ohms or more, repair open in FLI circuit

  72. 86) Check For Open In CASE GND Circuit

    Measure resistance between PCM connector pin No. 25 (CASE GND) and CASE GND terminal at fuel pump module wiring harness connector. Also measure resistance between PCM connector pin No. 25 (CASE GND) and fuel gauge ground terminal at instrument cluster wiring harness connector. If both resistance readings are less than 10,000 ohms, check fuel gauge. See appropriate INSTRUMENT PANELS article in ACCESSORIES & EQUIPMENT in appropriate lemon-25® manual. Repair as necessary. Clear DTCs. Repeat QUICK TEST . If DTC P0460 is still present, replace PCM. If any resistance reading is 10,000 ohms or more, repair open in CASE GND circuit.

  73. 87) Check For Open In CASE GND Circuit (Continental Only)

    Measure resistance between PCM connector pin No. 25 (CASE GND) and terminal No. 27 at virtual image instrument cluster C255 wiring harness connector. See Fig 20. If resistance is less than 10,000 ohms, repair or replace fuel gauge as necessary. Repeat QUICK TEST . If DTC P0460 is still present, replace PCM. If resistance is 10,000 ohms or more, repair open circuit.
    NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 87 to step 91). No test procedures have been omitted.

  74. 91) DTC P1441: Monitor Idle Air Control Duty Cycle-Flex Fuel EVAP System

    If Continuous Memory DTC P1507 is also present with DTC P1441, go to  TEST KE, step 30). If DTC P1507 is not also present, turn ignition on. Using scan tool, select IAC, TP and RPM PIDs from PID/DATA monitor menu. With engine at normal operating temperature, accessories off, and engine idling, IAC PID duty cycle should be 20-45 percent. Observe IAC and RPM PID values for indication of fault while wiggling IAC valve connector and wiring harness between IAC valve and PCM. Fault will be indicated by a sudden increase in engine RPM and a decrease in duty cycle. Observe TP PID value and rapidly depress and release throttle. A fault will be indicated by a slow return to idle. This may indicate a sticking IAC valve. If any faults are indicated, repair as necessary. If no faults are found, go to next step.

  75. 92) Visually Check EVAP System

    Turn ignition off. Check for kinked or pinched fuel vapor tubes/hoses between EVAP canister, EVAP canister purge valve and intake manifold. Check for cracked or damaged EVAP canister. Repair as necessary. After repair is complete, go to step  101). If no faults are indicated, go to next step.

  76. 93) Check Voltage To EVAP Canister Purge Valve

    Disconnect EVAP canister purge valve connector. Turn ignition on. Measure voltage between VPWR terminal at EVAP canister purge valve wiring harness connector and negative battery terminal. See Fig 8. If voltage is more than 10.5 volts, go to next step. If voltage is not more than 10.5 volt, repair open in VPWR circuit.

  77. 94) Check For Vacuum At EVAP Canister

    Disconnect fuel vapor-to-EVAP canister hose at EVAP canister. Connect a vacuum gauge to disconnected fuel vapor hose. Start engine and allow to idle for 5 minutes. Vacuum gauge reading should be zero in Hg. Using scan tool, select EVAPPDC PID from PID/DATA monitor menu. Ensure vacuum gauge can be seen by vehicle operator. Road test vehicle at 50-60 MPH. While observing PID value, hold throttle steady for 1-2 minutes with vehicle at a speed more than 50 MPH. When EVAPPDC PID value reaches 75-85 percent duty cycle, observe vacuum gauge reading. If vacuum gauge reading changes from about zero in Hg. to about 10 in Hg. with EVAPPDC PID at more than 75 percent, remove vacuum gauge. Inspect fuel vapor tubes/hoses between EVAP canister and EVAP canister purge valve for cracks, splits or holes. Also check fuel vapor tubes/hoses between EVAP canister purge valve and intake manifold. Repair as necessary and go to next step. If vacuum gauge reading does not change as specified, remove vacuum gauge. Leave fuel vapor hose disconnected. If vacuum gauge reading is 6-10 in Hg., go step  96). If vacuum gauge reading is less than 6 in Hg., go to step  97).

  78. 95) Check EVAP Canister

    Ensure fuel vapor-to-EVAP canister hose at EVAP canister is disconnected. Check all EVAP canister ports for contamination and blockage. Repair as necessary or replace EVAP canister. If no faults are found, go to next step.

  79. 96) Check For Fuel Vapor Hose Leak

    Disconnect other end of fuel vapor-to-EVAP canister hose at EVAP canister purge valve. See Fig 10 or Fig 11 . Plug open end of fuel vapor hose at EVAP canister. Connect a vacuum pump to open end of fuel vapor hose at EVAP canister purge valve. Apply 16 in Hg. to hose. If vacuum holds, remove plug from hose and go to next step. If vacuum does not hold, replace faulty fuel vapor hose and go to step  101).

  80. 97) Check For Fuel Vapor Hose Blockage

    Ensure both ends of fuel vapor hose at EVAP canister purge valve and EVAP canister are disconnected. Connect a vacuum pump to open end of fuel vapor hose at EVAP canister purge valve. Apply 16 in Hg. to hose. If vacuum holds, fuel vapor hose is blocked between EVAP canister and EVAP canister purge valve. Repair or replace hose as necessary. If vacuum does not hold, remove vacuum pump. Reconnect fuel vapor hose at both ends and go to next step.

  81. 98) Check For Intake Manifold Vacuum

    Disconnect input port vacuum (to intake manifold) hose at EVAP canister purge valve. See Fig 10 or Fig 11 . Connect a vacuum pump to input vacuum source port at EVAP canister purge valve. Apply 10-15 in Hg. If vacuum holds or releases very slowly, repair EVAP canister purge valve filter blockage or replace EVAP canister purge valve. If vacuum releases quickly, go to next step.

  82. 99) Check For Vacuum At EVAP Canister Purge Valve

    Connect EVAP canister purge valve connector. Disconnect input port vacuum (to intake manifold) hose and fuel vapor-to-intake manifold hose at EVAP canister purge valve. Connect a vacuum gauge to disconnected input port vacuum (to intake manifold) hose at EVAP canister purge valve. Start engine and note vacuum gauge reading. Disconnect vacuum gauge and connect gauge to disconnected fuel vapor-to-intake manifold hose at EVAP canister purge valve. Start engine and note vacuum gauge reading. If both vacuum gauge readings are more than 10 in Hg, go to next step. If both vacuum gauge readings are not more than 10 in Hg, repair cause of vacuum loss. After repair is complete, go to next step.

  83. 100) Check Vacuum Hose & Fuel Vapor Hose

    Disconnect input port vacuum (to intake manifold) hose and vapor hose-to-intake manifold hose at intake manifold. Other end of hoses are still disconnected from previous step. Connect a vacuum pump to each disconnected hose and apply 16 in Hg. If vacuum releases for both hoses, replace canister purge valve and go to next step. If vacuum does not release for one or both hoses, remove blockage or minor kinks in hose(s). After repair is complete, go to next step.

  84. 101) Check EVAP System Leak

    Odors in engine compartment or near exhaust system, and engine stalls can be associated to EVAP system. Possible causes are:
    • Aftermarket parts and accessories not conforming to EVAP system specifications.
    • Leaks in EVAP system.
    • Blockages in EVAP system.

    Remove atmospheric vent cap (Blue or Black) on EVAP canister(s) or canister vent line. Plug (or tape) open vent on EVAP canister(s). Disconnect and plug fuel vapor-to-intake manifold hose at intake manifold vacuum source. Locate evaporative test port (marked EVAPORATIVE SERVICE PORT) between EVAP canister purge valve and EVAP canister. If vehicle does not have a test port, go to next step. Install EVAP System Leak Tester (134-00056) including compressed gas source (nitrogen or argon) and pressure regulator to test port. Regulate gas pressure on tester to 27 in. H2 O. Using instructions provided with EVAP system leak tester, pressurize EVAP system. Follow system leak test instructions provided with tester. If system pressure holds, go to next step. If system pressure does not hold, check fuel filler cap for damage. Replace cap as necessary and retest. If fuel filler cap is okay, replace EVAP system components (fuel tank, fuel filler pipe, fuel vapor hoses, etc.) as necessary.

  85. 102) Check If Tester Indicates A Leak

    Remove fuel filler cap. Turn ignition on. On Mustang, using scan tool, cycle EVAP canister purge valve open by entering OUTPUT TEST MODE. On all models, regulate gas pressure on tester to 27 in. H2 O. Using instructions provided with EVAP system leak tester, pressurize EVAP system. Follow system leak test instructions provided with tester. If Red light on tester is on (indicating a system leak), go to next step. If Red light on tester is off, remove EVAP system leak tester. Clear DTCs. Using scan tool, select EVAPPDC PID from PID/DATA monitor menu. Road test vehicle 50-60 MPH until PID value reaches 75 percent duty cycle. Maintain vehicle speed until duty cycle reaches zero percent. Hold speed for an additional 2 minutes, then stop vehicle. Allow engine to idle. Retrieve Continuous Memory DTCs. Verify symptom no longer exists.

  86. 103) Check For Fuel Vapor Hose Restrictions

    Disconnect and plug fuel vapor-to-EVAP canister hose at EVAP canister purge valve. See Fig 10 or Fig 11 . Using EVAP system leak tester, pressurize EVAP system until system is stabilized close to 27 in. H2 O. Record pressure reading. Remove plug from fuel vapor-to-EVAP canister hose. If pressure drops immediately, remove all plugs and go to next step. If pressure does not drop immediately, locate and repair blockages between fuel tank, EVAP canister purge valve and EVAP canister(s). Remove all plugs and go to next step.

  87. 104) EVAP System Verification

    Clear DTCs. Remove fuel filler cap (if not already removed). Disconnect and plug fuel vapor-to-intake manifold hose at intake manifold vacuum source. Using EVAP system leak tester, pressurize EVAP system until system is stabilized at about 27 in. H2 O. Observe tester leak self-test for 2 minutes and then observe EVAP system leak test. Listen for vacuum leak noise and check for fuel vapor odors at isolated areas in EVAP system. If system does not hold pressure, go to next step. If system holds pressure, reconnect all components. Remove EVAP system leak tester. Clear DTCs. Using scan tool, select EVAPPDC PID from PID/DATA monitor menu. Road test vehicle 50-60 MPH until PID value reaches 75 percent duty cycle. Maintain vehicle speed until PID duty cycle reaches zero percent. Hold speed for an additional 2 minutes, then stop vehicle. Allow engine to idle. Retrieve Continuous Memory DTCs. Verify symptom no longer exists.

  88. 105) Determine EVAP System Leak

    Systematically isolate area of potential pressure leak. Close off pressure to EVAP system. Disconnect and plug fuel vapor hose from fuel tank at EVAP canister. Using EVAP system leak tester, pressurize EVAP system until system is stabilized close to 27 in. H2 O. If pressure now holds, replace EVAP canister. If system does not hold pressure, close off pressure to EVAP system. Disconnect and plug fuel vapor-to-EVAP canister hose at EVAP canister purge valve. Again, pressurize EVAP system until system is stabilized close to 27 in. H2 O. If system holds pressure, remove plugs. Reconnect fuel vapor hose at EVAP canister. Return to step  98) to check EVAP canister purge valve. Replace as necessary. Reconnect all components. Remove EVAP system leak tester. Clear DTCs. Using scan tool, select EVAPPDC PID from PID/DATA monitor menu. Road test vehicle 50-60 MPH until PID value reaches 75 percent duty cycle. Maintain speed until duty cycle reaches zero percent. Maintain speed for an additional 2 minutes, then stop vehicle. Allow engine to idle. Retrieve Continuous Memory DTCs. Verify symptom no longer exists. If system does not hold pressure, remove plugs. Check for fuel vapor hose cracks. Repair as necessary. Remove EVAP system leak tester. Clear DTCs. Using scan tool, select EVAPPDC PID from PID/DATA monitor menu. Road test vehicle 50-60 MPH until PID value reaches 75 percent duty cycle. Maintain vehicle speed until PID duty cycle reaches zero percent. Maintain speed for an additional 2 minutes, then stop vehicle. Allow engine to idle. Retrieve Continuous Memory DTCs. Verify symptom no longer exists.
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