Chart 1
- Stalls/Quits: Idle, Acceleration, Cruise, Stall After Start
- Runs Rough
- Misses
- Buck/Jerk
- Hesitation/Stumble
- Surge
- Unique Idle Concerns: Rolling Idle
- Intermittent Rough Idle
NOTE:
For some vehicle applications, the engine may stall if left running while refueling. Advise the customer to turn the engine off while refueling to avoid contamination or damage to the evaporative emission (EVAP) system.
| SYSTEM/COMPONENT | REFERENCE (PINPOINT TESTS -- GASOLINE MODELS unless noted) |
|---|---|
Check the following parameter identifiers (PIDs):
|
DPFEGR PID value not within 0.03 volt (E-Series 5.4L) or 0.15 volt (all others) of key ON, engine OFF value: For vehicles equipped with an exhaust gas recirculation system module (ESM), GO to Pinpoint Test HH . For all others, GO to Pinpoint Test HE . LONGFT1/LONGFT2 value low (-): Continue diagnosis. Concentrate checks in areas that would cause the engine to run rich. LONGFT1/LONGFT2 value high (+): Continue diagnosis. Concentrate checks in areas that would cause the engine to run lean. VPWR not between 10.5 and 17.0 volts: REFER to the appropriate CHARGING SYSTEM - GENERAL INFORMATION article . VPWR between 10.5 and 17.0 volts, but not within 0.5 volt of battery voltage: CHECK the B+ voltage to the powertrain control module (PCM) power relay. CHECK the VPWR circuit between the PCM and the PCM power relay. CHECK the PWR GND circuits. |
| For vehicles that run rough at idle: Check the INJxF PIDs (the "x" indicates the injector number) with the key ON, engine OFF. There is 1 INJxF PID for each engine cylinder. All INJxF PIDs must indicate no fault (or NO). |
The INJxF PID(s) indicate a fault (an injector circuit fault is indicated). For Ford GT, GO to Pinpoint Test HL . For all others, GO to Pinpoint Test KG . |
| Mass Air Flow (MAF) Sensor | GO to Pinpoint Test DC . |
| Secondary Ignition System | For vehicles equipped with a coil pack ignition system, GO to Pinpoint Test JC
. For all others, GO to Pinpoint Test JB . |
| Fuel Delivery System | GO to Pinpoint Test HC . |
| Exhaust System | GO to Pinpoint Test HF . |
| Positive Crankcase Ventilation (PCV) System | GO to Pinpoint Test HG . |
| EVAP System | GO to Pinpoint Test HX . |
| Charging System | GO to Pinpoint Test HY . |
| Automatic Transmission | REFER to the appropriate AUTOMATIC TRANSMISSION article . |
| Base Engine | REFER to the appropriate ENGINE article . |
| Intake Air System (for vehicles equipped with an idle air control [IAC] valve) | GO to Pinpoint Test HU . |
| A/C Pressure (ACP) Sensor | GO to Pinpoint Test DS . |
| Additional Testing | GO to Pinpoint Test Z . |
Additional Checks:
|
REFER to the applicable service information article. |