Common Symptoms
- Hard starting in cold weather
- Extended cranking time before engine starts
- White smoke from exhaust on cold start
- Engine runs rough immediately after cold start
- Check engine light illuminated
- Glow plug indicator lamp may flash or stay on
Most Likely Root Causes
- Failed glow plug on cylinder 8
- Open or short circuit in glow plug wiring harness
- Corroded or damaged glow plug connector
- Failed glow plug control module or relay
- Poor ground connection at glow plug circuit
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Component Location
Cylinder 8 glow plug is installed in the cylinder head on the number 8 cylinder, accessible from the valve cover side of the engine.
Manufacturer Notes
Diesel engines may set individual cylinder glow plug codes when one or more glow plugs fall outside normal operating parameters.
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