Dieseling, Run on

DEFINITION:
Engine continues to run after key is turned "OFF", but runs very roughly. If engine runs smoothly, check ignition switch and adjustment.

CHECK
- Fuel injector leaking

- Obvious overheating problems, 85°C - 100°C (185°F - 215°F) is normal.
- Low coolant.
- Loose water pump belt.
- Restricted air flow to radiator, or restricted water flow thru radiator.
- Faulty or incorrect thermostat.
- Correct coolant solution - should be a 50/50 mix of anti-freeze/coolant and water.