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For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1999 🢒 Alero 🢒 Engine 🢒 Engine Mechanical - 2.4L 🢒 Cuts Out, Misses

Cuts Out, Misses

Checks

Action

DEFINITION: Steady pulsation or jerking that follows engine speed, usually more pronounced as engine load increases.

Preliminary
    •  Refer to Symptoms .
    •  Search for service bulletins.

Fuel System
    • Check system fuel pressure. Refer to Fuel System Diagnosis .
    • Check the fuel injectors. Refer to Fuel Injector Balance Test .
    • Check for contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
    • Check the fuel filter for being plugged or restricted.
    • Check items which can cause an engine to run rich (long term fuel trim significantly in the negative range). Refer to Diagnostic Aids for DTC P0172 Fuel Trim System Rich .
    • Check items that can cause an engine to run lean (long term fuel trim significantly in the positive range). Refer to Diagnostic Aids for DTC P0171 Fuel Trim System Lean .
    • Check for proper operation of the Evaporative Emission (EVAP) control system. Refer to Evaporative Emission Control System Diagnosis .
    • Check for fuel in the Fuel Pressure Regulator vacuum hose.

Sensor/System
    • Check the Oxygen sensor (O2S 1). The O2S 1 should respond quickly to different throttle positions. If not, check the O2S 1 for silicon or other contaminants from fuel or the use of improper RTV sealant. The sensor may have a white powdery coating. Silicon contamination causes a high but false O2S 1 signal voltage (rich exhaust indication). The PCM will reduce the amount of fuel delivered to the engine, causing a severe driveability problem. Refer to Oxygen sensor in Information Sensors/Switches Description .
    • Check the EGR valve for a stuck open pintle.
    • Check for proper operation of the MAP Sensor. Refer to Manifold Absolute Pressure Sensor Output Diagnosis .
    • Check for proper operation of the TP sensor.
    • Check for proper operation of the ECT sensor.

Ignition System
    • Check for proper ignition voltage output with the J 36012-A spark plug jumper wires and J 26792 spark tester or equivalent.
    • Check the spark plugs for the following conditions:
       - Check for wet or fuel fouled spark plugs.
       - Check for cracks on the spark plugs.
       - Check for wear.
       - Check for improper spark plug gap.
       - Check for burned electrodes or heavy deposits.
    • If the spark plugs are fuel or oil fouled, the cause of the fouling must be determined before replacing the spark plugs.
    • Check the Ignition Control Module (ICM) for proper ground connection.
    • Check the ignition coils for cracks or carbon tracking.
    • Check the ignition coil housing internal or external for cracks or carbon tracking.

Engine Mechanical
    • Check the following:
       - Sticking or leaking valves.
       - Worn camshaft lobe(s).
       - Valve timing.
       - Broken valve springs.
       - Excessive oil in combustion chamber-Leaking valve seals.
       - Proper oil viscosity.
       - Low cylinder compression.
    • For incorrect basic engine parts. Inspect the following:
       - Camshafts
       - Cylinder head
       - Pistons, etc.
    • Refer to Engine Mechanical.

Additional Checks
    • Check exhaust system for possible restrictions. Check for the following:
       - Inspect exhaust system for damaged or collapsed pipes.
       - Inspect mufflers for heat distress or possible internal failure.
       - For possible plugged Three-Way catalytic converter. Refer to Restricted Exhaust System Check .
    •  An engine miss condition can be caused by Electromagnetic Interference (EMI) on the reference circuit. EMI can usually be detected by monitoring engine RPM with a scan tool. A sudden increase in RPM with little change in actual engine RPM change, indicates EMI is present. If a problem exists, check routing of secondary ignition wires, high voltage components (Near Ignition Control circuits).
    • Check for intake and exhaust manifold passages for casting flash. Refer to Engine Mechanical .
    • Check for malfunctioning engine mounts. Refer to Engine Mechanical .
    • An intermittent may be caused by the following conditions:
       - Poor electrical connections.
       - Rubbed through wire insulation.
       - Wire broken inside the insulation.
    • Any circuitry that is suspected as causing an intermittent complaint should be thoroughly checked for the following conditions:
       - Backed out terminals.
       - Improper mating of terminals.
       - Improperly formed or damaged terminals.
       - Poor terminals to wiring electrical connections.
       - Physical damaged to the wiring harness.
       - Corrosion.