Common Symptoms
- Check engine light illuminated
- Hard starting or extended cranking in cold weather
- Rough idle or engine misfires when cold
- White smoke from exhaust on cold starts
- Engine hesitation or stumbling during warm-up
Most Likely Root Causes
- Faulty cylinder 3 glow plug
- Open or short circuit in glow plug wiring harness
- Corroded or loose glow plug connector
- Failed glow plug control module or relay
- Damaged glow plug tip or internal heating element failure
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Component Location
Cylinder 3 glow plug is threaded into the cylinder head near the fuel injector for cylinder 3.
Manufacturer Notes
Some diesel engines require updated glow plug control module software to address false fault codes on high-mileage vehicles.
Also diagnosing J1939 SPN/FMI codes?
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