P0674: Cylinder 4 Glow Plug Circuit/Open
What to do
Driveable, with hard cold starting. If faults are stored for several cylinders at once, the module or its supply is more likely than several failed plugs.
What this code means
A circuit fault on cylinder 4's glow plug. Diagnosed as P0671. On a four-cylinder engine this is the last of the set, and several of these codes appearing together points at the control module or its supply rather than at four simultaneously failed plugs.
Likely causes
Start here
- Failed glow plug · moderate
- Corroded or loose connector · easy
- Broken glow plug supply wire · moderate
Less common
- Failed glow plug control module · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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