Common Symptoms
- Hard starting in cold weather
- Extended cranking time before engine starts
- White smoke from exhaust on cold start
- Engine misfires or runs rough until warmed up
- Check engine light illuminated
- Glow plug warning light flashing or staying on
Most Likely Root Causes
- Failed glow plug on cylinder 6
- Damaged or corroded wiring to cylinder 6 glow plug
- Faulty glow plug control module or relay
- Loose or corroded connector at glow plug
- Internal short circuit in glow plug harness
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Component Location
Cylinder 6 glow plug is threaded into the cylinder head on the number 6 cylinder, typically accessed from the valve cover side.
Manufacturer Notes
Some diesel engines require specific glow plug replacement procedures to avoid damage to cylinder head threads.
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