Cuts Out/Misses

Definition: Steady pulsation or jerking that follows engine speed, usually more pronounced as engine load increases. The exhaust has a steady spitting sound at idle or low speed.

Perform careful visual and physical check as described at the beginning of Symptoms.

Perform "Diagnostic Circuit Check."

^ CHECK
- Ignition wires for shorts or faulty insulation.
- Ignition system for moisture, dust, cracks, burns, etc. Spray plug wires with fine water mist to check for shorts.
- For possibility of misfiring, crossfiring, or cutting out under load or at idle. If present, refer to the "Ignition System Check" Chart. Chart C-4C Ignition System Check (Remote Coil)
- Secondary ignition voltage output with J 26792 (ST-125) spark tester or equivalent.
- Ignition coil connections.
- ECM and ignition system for faulty grounds.
- Proper operation of EST.
- Spark plugs. Look for wear, wetness, cracks, improper gap, burned electrodes, and heavy deposits.
- Spark plugs for correct heat range
- For improper crank sensor resistance or faulty connections.
- Fuel for poor quality, "stale" fuel, and water contamination.
- Fuel system for restricted filter or improper pressure. Use CHART A-7. Chart A-7 Fuel System Pressure Test
- Fuel shut-off due to overboost. Use Code 31 chart. Powertrain Controls - ECM/PCM
- Throttle shaft or TPS for sticking or binding. TPS voltage should read less than 1.25 volts on a Scan" tool with the throttle closed.
For possibility of misfiring, crossfiring, or cutting under load or at idle. Locate misfiring cylinder(s) by performing the following test.
1. Start engine. Disconnect idle air control valve. Remove one spark plug wire from a spark plug and ground it against the engine.
2. Note drop in engine speed.
3. Repeat for all six cylinders.
4. Stop engine and reconnect idle air control valve.
If the engine speed dropped equally (within 50 rpm) on all cylinders, refer to "Rough, Unstable, or Incorrect Idle, Stalling" symptom. If there was no drop or excessive variation in engine speed on one or more cylinders, check for spark on the respective cylinder(s) with J 26792 (ST- 125) spark tester or equivalent. If there is no spark, refer to IGNITION SYSTEM. Ignition System
If spark is present, remove the spark plugs from the cylinder(s) and check for the following.
Cracks
Wear
Improper gap
Burned electrode
Heavy deposits
Wetness