Common Symptoms
- Check engine light illuminated
- Rough idle or engine vibration
- Loss of power or hesitation during acceleration
- Poor fuel economy
- Engine stumbling or surging under load
- Raw fuel smell from exhaust
Most Likely Root Causes
- Faulty ignition coil on cylinder 7
- Worn or fouled spark plug
- Fuel injector failure or clogging
- Low compression in cylinder 7
- Vacuum leak affecting cylinder 7
- Damaged spark plug wire or boot
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Component Location
Cylinder 7 is typically located on the driver side rear of V6/V8 engines or seventh position on inline engines.
Manufacturer Notes
Some V8 engines may require updated ignition coils or spark plugs to address persistent misfire concerns on rear cylinders.
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