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Home >> Oldsmobile >> 1998 >> Regency >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Diagnostic Procedures - 3.8L >> No Start Diagnosis >> No Start - Engine Cranks Okay (VIN K & 1 With C(3)I) >> Ignition System (VIN K & 1)

Ignition System (VIN K & 1)

  1. Perform On-Board Diagnostic (OBD) System Check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. After performing OBD system check, go to next step.
  2. Turn ignition on. Using scan tool, select FAILED SINCE CODE CLEAR function. If Diagnostic Trouble Code (DTC) P0123, P0601, P0602, P1626 or P1629 is present, diagnose DTC(s). See TESTS W/CODES article. If DTC(s) is not present, go to next step.
  3. Check Ignition Control Module (ICM) ignition feed circuit fuse and fuel injector ignition feed circuit fuse. If either fuse is blown, locate and repair short to ground in suspect ignition feed circuit. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If fuses are okay, go to next step.
  4. Using scan tool, observe engine speed display while cranking engine. If RPM is indicated, go to next step. If RPM is not indicated, go to step 24).
  5. Turn ignition off. Disconnect injector connector. Install Injector Test Light (J-34730-2A) to injector connector. See WIRING DIAGRAMS article. Turn ignition on and observe injector test light. If injector test light illuminates, go to step 17). If injector test light does not illuminate, go to next step.
  6. Crank engine and monitor injector test lights. If all injector test lights flash, go to next step. If any injector test light does not flash, go to step 19).
  7. Turn ignition off. Install fuel pressure gauge to fitting on fuel rail. Turn ignition on and observe fuel pressure. Fuel pressure should be 48-55 psi (3.4-3.8 kg/cm2 ) and hold steady. If fuel pressure is as specified, go to step 9). If fuel pressure is not as specified, go to next step.
  8. If fuel pressure is indicated, but not as specified, diagnose fuel system. See BASIC FUEL SYSTEM CHECKS  . If fuel pressure is not present, go to FUEL SYSTEM ELECTRICAL CIRCUIT.
  9. Check for fuel contamination. If fuel is contaminated, clean fuel system. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in G - TESTS W/CODES article. If fuel is not contaminated, go to next step.
  10. Install Spark Tester (J-26792) to cylinder No. 1, 2 and 3 (one at a time). Connect the spark plug wire of companion cylinder to ground (i.e., 1/4, 2/5, 3/6). Crank engine and observe spark tester. If spark is present, go to next step. If spark is not present, go to step 12).
  11. Remove and inspect spark plugs from all cylinders. If spark plugs are okay, go to step 36). If spark plugs shows excessive fouling, check engine for mechanical problems.
  12. If spark is present at any ignition wire, go to next step. If spark is not present at any ignition wire, go to step 25).
  13. Remove and inspect ignition coil to affected cylinder for cracks or carbon tracking. Replace faulty ignition coil(s) as necessary. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If coil(s) are okay, go to next step.
  14. Check secondary ignition coil resistance. Resistance should be 5000-8000 ohms. Replace faulty ignition coil(s) as necessary. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If resistance is as specified, go to next step.
  15. Check resistance of ignition wire associated with cylinder that did not produce a spark. On VIN K, resistance should be 10,000 ohms. On VIN 1, resistance should be 7000 ohms. Replace suspect ignition wire if resistance is greater than specified. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If resistance is as specified, go to next step.
  16. Connect test light across Ignition Control Module (ICM) primary circuit (between ICM control terminals) for coils associated with cylinder that did not produce a spark. Crank engine. If test light flashes, go to step 39). If test light does not flash, go to step 40).
  17. Turn ignition off. Disconnect Powertrain Control Module (PCM) connector. Turn ignition on. Observe injector test lights. If injector test lights illuminate, go to next step. If injector test lights does not illuminate, go to step 38).
  18. Locate and repair short to ground in injector control circuit(s) to affected injector (test light stayed on). See WIRING DIAGRAMS article. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article.
  19. If any injector test light flashes, go to next step. If no injector test light flashes, go to step 22).
  20. Disconnect injector test light that did not flash when engine was being cranked. Turn ignition on. Using a test light connected to ground, probe ignition feed circuit at each injector connector. See WIRING DIAGRAMS article. If test light illuminates on all injector connectors, go to next step. If test light does not illuminate on all injector connectors, go to step 34).
  21. Turn ignition off. Disconnect Powertrain Control Module (PCM) connector. Check affected injector circuit driver for an open. See WIRING DIAGRAMS article. Repair open circuit as necessary. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If circuit is okay, go to step 38).
  22. Using a test light connected to ground, probe fuel injector ignition feed terminal at any injector connector. See WIRING DIAGRAMS article. If test light illuminates, go to next step. If test light does not illuminate, go to step 34).
  23. Install an injector test light to any injector connector. Turn ignition off. Disconnect Ignition Control Module (ICM) connector. Turn ignition on. Using a test light connected to battery voltage, repeatedly touch test light to 3X reference circuit at ICM connector. See WIRING DIAGRAMS article. If injector test light flashes, go to next step. If injector test light does not flash, go to step 33).
  24. Turn ignition off. Disconnect Ignition Control Module (ICM) connector. Turn ignition on. Using a test light connected to ground, probe ignition control module ignition battery voltage terminal. See WIRING DIAGRAMS article. If test light illuminates, go to next step. If test light does not illuminate, go to step 35).
  25. Using a fused jumper wire, jumper Crankshaft Position (CKP) sensor ignition battery voltage circuit at ICM connector to battery voltage. Connect a second jumper between ground and CKP sensor ground circuit at ICM connector. Connect DVOM between battery voltage and CKP sync signal circuit at ICM connector. Crank engine and observe DVOM voltage reading. Voltage should be 1-3 volts. If voltage reading is as specified, go to step 29). If voltage reading is not as specified, go to next step.
  26. If voltage reading is greater than 3 volts, go to next step. If voltage reading is less than 3 volts, go to step 28).
  27. Disconnect CKP sensor connector. Using a test light connected to battery voltage, probe CKP sync signal circuit. See WIRING DIAGRAMS article. If test light illuminates, locate and repair short to ground in CKP sync signal circuit. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If test light does not illuminate, go to step 41).
  28. Check open or short to voltage in CKP sync signal circuit, open in CKP sensor ground circuit, or open or short to ground in CKP sensor ignition positive voltage circuit. See WIRING DIAGRAMS article. Repair as necessary. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If no circuit problems are found, go to step 41).
  29. Connect DVOM between battery voltage and 18X reference circuit at ICM connector. Crank engine and observe DVOM voltage reading. Voltage should be 5-7 volts. If voltage reading is as specified, go to step 40). If voltage reading is not as specified, go to next step.
  30. If voltage reading is greater than 7 volts, go to next step. If voltage reading is less than 7 volts, go to step 32).
  31. Disconnect CKP sensor connector. Using a test light connected to battery positive, probe 18X reference circuit terminal. See WIRING DIAGRAMS article. If test light illuminates, locate and repair short to ground in 18X reference circuit. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If circuit is okay, go to step 41).
  32. Check for open or short to voltage in 18X reference circuit. Repair as necessary. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If circuit is okay, go to step 41).
  33. Turn ignition off. Disconnect PCM connector. Check for open or short in 3X reference circuit. Repair as necessary. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If circuit is okay, go to step 38).
  34. Locate and repair open in fuel injector ignition positive voltage circuit. See WIRING DIAGRAMS article. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article.
  35. Locate and repair open in ICM ignition positive voltage circuit. See WIRING DIAGRAMS article. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article.
  36. Check for a stuck Throttle Position (TP) sensor, stuck or skewed Manifold Absolute Pressure (MAP) sensor, or faulty Engine Coolant Temperature (ECT) sensor. Repair or replace as necessary. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article. If sensors are okay, go to next step.
  37. Repair engine mechanical problem. Check for bent push rods, faulty or incorrect camshaft, leaking or sticky valves or rings, excessive valve deposits, loose or worn rocker arms, weak valve springs, incorrect valve timing or a leaking head gasket. Repair as necessary. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article.
  38. Replace PCM. Perform PCM relearn procedures. After replacing PCM, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article.
  39. Replace affected ignition coil(s) that did not produce a spark. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article.
  40. Replace ICM. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article.
  41. Replace CKP sensor. After repairs, perform ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK in TESTS W/CODES article.
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