Dieseling/Run-on

Symptom: Engine continues to run after ignition key is switched to the "OFF" position, but runs roughly.

POSSIBLE CAUSE ACTION

COOLING SYSTEM MALFUNCTION - Check for obvious over heating problems, low engine coolant level and leaks, water pump operation, loose belts, Faulty or incorrect thermostat, restricted air flow to radiator or restricted coolant flow, incorrect coolant solution (should be 50/50), proper fan operation (electric or belt driven).

FUEL SYSTEM MALFUNCTION - Check fuel injectors for leakage, Perform injector leak down test.

- Check idle speed, verify Idle Air Control (IAC) motor is operating properly.

EMISSIONS COMPONENT MALFUNCTION - Check Evaporative control system.

ENGINE MECHANICAL MALFUNCTION - Check for carbon buildup on pistons. Remove carbon with top engine cleaner. Follow instructions on can.

- Check for excessive oil entering combustion chambers.