Diagnostic Aids
WARNING: This page is about a different variant/trim than selected.
- A misfire may only occur when the engine is under a load or when the engine is cold.
- A misfire DTC may be caused by an excessive vibration from sources other than the engine. Inspect for the following possible sources:
- A tire or wheel that is out of round or out of balance
- Variable thickness brake rotors
- Certain rough road conditions
- A damaged accessory drive component or belt-Remove the drive belt and safely operate the engine to evaluate.
- A damaged reluctor wheel
- High resistance in the circuits of the injectors may set a misfire DTC without setting an injector DTC. Test the injector circuits of the affected cylinder(s) for a high resistance if you suspect a condition.
- If the condition is intermittent, observing the scan tool IC Circuit Test and Fuel Injector Circuit Test Status parameters may help to isolate the condition. The circuit status parameters will change from OK or Not Run to Malfunction if a condition exists.
- A condition in HO2S heater control circuits may set a misfire DTC.