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For 1990-2009 cars only

Cuts Out, Misses Symptom

Checks

Action

DEFINITION: A steady pulsation or jerking that follows engine speed, usually more pronounced as the engine load increases. The exhaust has a steady spitting sound at idle, low speed or on hard acceleration.

Preliminary Checks

    • Refer to Symptoms .

Sensor Checks

Inspect the mass air flow (MAF) sensor operation. Run the engine to normal operating temperature. Turn OFF all accessories and observe the MAF sensor at idle with a scan tool. If the MAF sensor reading is more than 3.5 g/s refer to DTC P0101 Mass Air Flow (MAF) Sensor Performance .

Fuel System Checks

    • Check for a restricted fuel filter or an incorrect fuel pressure. Refer to Fuel System Diagnosis .
    • Check the fuel injectors. Perform the Fuel Injector Coil Test procedure and the Fuel Injector Balance Test procedure. Refer to Fuel Injector Solenoid Coil Test - Engine Coolant Temperature Between 10-35 Degrees C (50-95 Degrees F) and to Fuel Injector Balance Test .
    • Check for water contamination of the fuel.

Ignition System Checks

    • Check for an ignition system misfire:

        Important: Do not perform this test for more than 2 minutes in order to prevent damage to the catalytic converter.

        1. Start the engine.
        2. Remove one ignition coil at a time using insulated pliers.
        3. If there is an RPM drop on all cylinders (equal to within 50 RPM), refer to Rough, Unstable, or Incorrect Idle and Stalling .
        4. Check for spark on the suspected cylinders with a J 26792 spark tester or equivalent if there is no RPM drop on one or more cylinders.
        5. If there is no spark, refer to Engine Cranks but Does Not Run .
        6. If there is spark, check the spark plugs for any of the following conditions:
       - Any wet or fuel fouled plugs
       - A terminal screw that is bent or loose
       - A ceramic insulator that has cracks, carbon tracking, or red or black dust deposits.
       - A tip insulator that has cracks or carbon tracking, any oil, carbon, glazing, or fuel additive deposits, or is loose.
       - A center electrode that is loose and wiggles side to side.
       - An incorrect spark plug gap
       - Missing platinum pads
    • Check the ignition coil boots for carbon tracking or cracks.
    • Check the ignition system for moisture, dust, cracks, burns, etc.

Engine Mechanical Checks

    • Check for any of the following engine mechanical problems:
       - Any faulty hydraulic lifter assemblies
       - Any broken or weak valve springs
       - An incorrect valve timing
       - An incorrect or worn camshaft
    • Check the intake and exhaust manifold passages for casting flash.
    • Refer to Engine Mechanical.

Additional Checks

    • An engine miss condition can be caused by electromagnetic interference (EMI) on the reference circuit. EMI can usually be detected by monitoring the engine RPM with a scan tool. A sudden increase in RPM with little change in the actual engine RPM change indicates EMI is present. If a problem exists, check the routing of the secondary ignition wires and the high voltage components.