Common Symptoms
- Check engine light illuminated
- Rough idle or engine vibration
- Loss of power or hesitation during acceleration
- Increased fuel consumption
- Engine running rough under load
- Flashing check engine light under severe misfire
Most Likely Root Causes
- Faulty spark plug or ignition coil on cylinder 6
- Fuel injector failure or clogging on cylinder 6
- Low compression in cylinder 6
- Vacuum leak affecting cylinder 6
- Worn or damaged spark plug wire or boot
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Component Location
Cylinder 6 is typically the rearmost cylinder on the passenger side of V6/V8 engines or the sixth cylinder from front on inline engines.
Manufacturer Notes
Some manufacturers require updated PCM calibration or specific spark plug gap specifications for proper cylinder misfire detection accuracy.
Also diagnosing J1939 SPN/FMI codes?
Heavy-duty trucks often throw both OBD-II and J1939 faults simultaneously. AI Diesel Tech handles both protocols in a single guided session.
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