Common Symptoms
- Hard starting in cold weather
- Rough idle until engine warms up
- White smoke from exhaust on cold start
- Glow plug indicator light stays on or flashes
- Engine hesitation during warm-up period
Most Likely Root Causes
- Faulty cylinder 7 glow plug
- Damaged wiring or connector to cylinder 7 glow plug
- Failed glow plug control module or relay
- Corroded glow plug terminals or connectors
- Excessive carbon buildup on glow plug tip
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Component Location
Cylinder 7 glow plug is threaded into the cylinder head on the number 7 cylinder, typically accessed from the valve cover side.
Manufacturer Notes
Some diesel engines require glow plug replacement in complete sets to ensure uniform heating characteristics across all cylinders.
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