Cuts Out, Misses. Geo Prizm 1997

For 1990-2009 cars

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 Powertrain On Board Diagnostic (OBD) System Check .

• | Refer to Symptoms .

Ignition System Checks

• | Check for a 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 spark plug wire at a time, using insulated pliers.

3. | If there is a 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 cylinder(s) with a spark tester (J 26792 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:

- | Wet (fuel fouled) plugs.

- | A terminal screw that is bent or loose (rotate and pull).

- | A ceramic insulator that has cracks, carbon tracking or deposits (red or black dust)

- | A tip insulator that has cracks, carbon tracking, deposits (oil, carbon, glazing, fuel additive), or is loose (rattles).

- | A center electrode that is loose (wiggles side to side)

- | An incorrect spark plug gap that is too large or too small.

- | Platinum pads that are missing.

• | Check the spark plug wire resistance (should not exceed 25,000 ohms).

• | Check the ignition coils for carbon tracking, cracks.

• | Check the ignition system for moisture, dust, cracks, burns, etc.

• | Run the engine and spray the secondary ignition system with water in order to check for shorts.

Engine Mechanical Checks

• | Check for any of the following engine mechanical problems:

- | Faulty hydraulic lifter assemblies

- | Broken or weak valve springs

- | Incorrect valve timing

- | Incorrect or worn camshaft

• | Check the intake and exhaust manifold passages for casting flash.

• | Refer to Engine Mechanical.

Fuel System Checks

• | Check for a restricted fuel filter or incorrect fuel pressure. Refer to .

• | 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 Fuel Injector Balance Test .

• | Check for water contamination of the fuel.