Rough, Unstable, Incorrect Idle, Stalling

SYMPTOM DESCRIPTION:

Engine runs unevenly at idle. If bad enough, the vehicle may shake. Also, the idle may vary in RPM (called "hunting"). Either condition may be severe enough to cause stalling. Engine idles at incorrect speed.


POSSIBLE CAUSE ACTION



Voltage Output - Check for proper secondary output voltage with spark tester.


Spark plugs - Check for wet plugs, cracks, wear, improper gap, burned electrodes or heavy deposits.


Secondary Wires - Check for bare or shorted wires. Check secondary wire resistance.


Distributor Cap - Check for moisture.


Distributor - Check for excessive shaft wear.


Distributor Pick-up Coil - Check resistance and connections.


Ignition Coil - Check resistance and connections.