Ignition System Checks
Check for an ignition system misfire.
CAUTION:
Do not perform this test for more than 2 minutes in order to prevent damage to the catalytic converter.
- Start the engine.
- Remove one ignition coil at a time using insulated pliers.
- If there is an RPM drop on all cylinders (equal to within 50 RPM), see ROUGH, UNSTABLE, OR INCORRECT IDLE AND STALLING .
- Check for spark on the suspected cylinders with Spark Tester (J 26792), or equivalent, if there is no RPM drop on one or more cylinders.
- If there is no spark, see ELECTRONIC IGNITION SYSTEM DIAGNOSIS under IGNITION SYSTEMS in SYSTEM & COMPONENT TESTING article.
- If there is spark, inspect the spark plugs for correct operation and good ignition system performance.
Check the ignition system for moisture, dust, cracks, burns, etc.