Diagnostic Aids
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- Excessive vibration from sources other than the engine can cause a misfire DTC. The following are possible sources of vibration:
- Variable thickness brake rotor.
- Drive shaft not balanced.
- Worn or damaged accessory drive belt.
- There may be more or less cylinders actually misfiring than indicated by the scan tool.
- Spray water on the secondary ignition components using a spray bottle. Look and listen for arcing or misfiring.
- If there are multiple misfires on only one bank, inspect the fuel injector and ignition coil, power and ground circuits for that bank.