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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2001 🢒 Firebird 🢒 Engine 🢒 Engine Controls - 5.7L 🢒 Cuts Out, Misses

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DEFINITION : A steady pulsation or jerking that follows engine speed. The condition is usually more pronounced as engine load increases. This condition is not normally felt above 1500 RPM, or 48 km/h (30 mph). The exhaust has a steady sputtering sound during idle or during low speed.

Preliminary
    • Refer to Important Preliminary Checks Before Starting in Symptoms - Engine Controls .
    • Search for bulletins.
    • Inspect the powertrain control module (PCM) grounds. Ensure that they are clean, tight, and in the proper locations. Refer to Engine Controls Schematics .
    • Remove the air filter element. Inspect the air filter element for dirt or for restrictions. Refer to Air Cleaner Element Replacement . Replace the element as necessary.

Fuel System
    • Inspect the fuel injectors. Refer to Fuel Injector Solenoid Coil Test .
    • Test for incorrect fuel pressure. Refer to Fuel System Diagnosis .
    • Test for a restricted fuel filter. Refer to Fuel System Diagnosis .
    • Test for a contaminated fuel condition. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
    • Inspect for conditions that cause an engine to run rich, with a long term fuel trim near -13 percent. For a rich condition, refer to DTC P0132 or P0152 .
    • Inspect for conditions that can cause an engine to run lean, with a long term fuel trim near 24 percent. For a lean condition, refer to DTC P0131 or P0151 .

Sensor/System

Use a scan tool in order to monitor the KS system for excessive spark retard activity. Refer to Knock Sensor (KS) System Description .

Ignition System
    • Wet the secondary ignition system with water from a spray bottle. Wetting the secondary ignition system may help to locate damaged or deteriorated components. When you apply the water, look and listen for arcing or for misfiring.
    • Test for proper ignition voltage output with spark tester J 26792 . Refer to Electronic Ignition (EI) System Diagnosis .
    • Remove the spark plugs. Inspect for the following conditions:
       - The correct heat range
       - Wet plugs
       -  Cracks
       -  Wear
       -  Improper gap
       -  Burned electrodes
       -  Heavy deposits
       - Refer to DTC P0131 or P0151 in Engine Electrical.
    • An improper spark plug gap causes a driveability condition. Gap the spark plugs using a wire gauge gap tool. Refer to Spark Plug Replacement in Engine Electrical.
    • Before you replace the spark plugs, determine the cause of the fouling. If the spark plugs are gas-fouled, refer to DTC P0172 or P0175 . If the spark plugs are oil-fouled or coolant-fouled, refer to Oil Consumption Diagnosis in Engine Mechanical-5.7L or Loss of Coolant in Engine Cooling.
    • Inspect the secondary ignition for the following conditions:
       - Ignition wires arcing to ground
       - Ignition wires for routing properly
       - Ignition coils for cracks, or for carbon tracking

Engine Mechanical
    • Inspect the engine mechanical components for the following conditions:
       - Test the engine compression. Refer to Engine Compression Test in Engine Mechanical-5.7L.
       - Sticking or leaking valves
       - Worn camshaft lobes
       - Valve timing
       - Bent push rods
       - Worn rocker arms
       - Broken valve springs
       - For specific symptoms, refer to Symptoms - Engine Mechanical in Engine Mechanical-5.7L.
       - Excessive oil in combustion chamber due to leaking valve seals. Refer to Oil Consumption Diagnosis in Engine Mechanical-5.7L.
    • Inspect for incorrect basic engine parts. Inspect the following components:
       - The camshaft
       - The cylinder heads
       - The pistons
       -  For specific diagnosis procedures, refer to Engine Mechanical-5.7L .

Additional Checks
    • Inspect the exhaust system for possible restrictions. Inspect for the following conditions:
       - Inspect the exhaust system for damaged or collapsed pipes. Refer to Restricted Exhaust in Engine Exhaust.
       - Inspect the mufflers for heat distress, or for possible internal failure. Refer to Exhaust Leakage in Engine Exhaust.
       - Inspect for possible plugged 3-way catalytic converters by comparing the exhaust system back pressure on each side of the engine. Refer to Restricted Exhaust in Engine Exhaust.
    • Electromagnetic Interference (EMI) on the reference circuit can cause an engine miss condition A sudden increase in the RPM, with little change in the actual engine RPM change indicates that EMI is present. If this condition exists, inspect for high voltage components near the ignition control circuits.
    • Inspect the intake manifold and the exhaust manifold passages for casting flash. Refer to Exhaust Manifold Cleaning and Inspection and Intake Manifold Cleaning and Inspection in Engine Mechanical-5.7L.