Common Symptoms
- Hard starting or extended cranking in cold weather
- White smoke from exhaust on cold start
- Rough idle until engine warms up
- Check engine light illuminated
- Glow plug warning light on or flashing
Most Likely Root Causes
- Failed cylinder 5 glow plug
- Open or shorted glow plug circuit wiring
- Corroded or loose glow plug connector
- Failed glow plug control module or relay
- High resistance in glow plug harness
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Component Location
Cylinder 5 glow plug is threaded into the cylinder head on the number 5 cylinder, typically accessed from the top or side of the engine.
Manufacturer Notes
Some diesel engines use individual glow plug control circuits that can isolate single cylinder faults without affecting other cylinders.
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