Possible causes

– Faulty cylinder #7 glow plug
– Cylinder #7 glow plug harness is open or shroted
– Cylinder #7 glow plug circuit poor electrical connection
– Faulty glow plug module

When is the code detected?

The Engine Control Module (ECM) has detected a fault in the cylinder #7 glow plug circuit

Symptoms

– Engine Light ON (or Service Engine Soon Warning Light)
– Lack/Loss of Power
– The engine may be harder to start
– Engine hesitation

P0677 Information for specific makes

P0677 FORD
P0677 GMC
P0677 VOLKSWAGEN