P2304
PowertrainIgnition Secondaryhigh severityIgnition Coil D Secondary Circuit
What P2304 Means
Fault in ignition coil D secondary circuit (typically cylinder 4).
Symptoms
- Cylinder 4 misfire
- Check engine light
- Engine shaking
Common Causes
- Failed coil
- Spark plug fouled
- Carbon tracking
Diagnostic Steps
- Coil swap test
- Plug inspection
- Check for oil in spark plug well
Where to start: Replace coil. Check valve cover gasket if oil in plug well.
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