GM Repair Questions? Ask a Mechanic for Answers ASAP
d0nt look like either 0f those there smooth just black soot
Ok, there is some info on some common causes for glow plugs burning out. first of all, all the battery cables at batteries must clean and tight.
There are certain electrical concerns that may induce the glow plug to go open. If the glow plug system senses a certain electrical "noise" on the power feed, it could induce glow plug concerns. This electrical "noise" may be induced by jump starting, loose connections, disconnecting the batteries with the ignition in the ON position, or a battery charger being used during a module reprogramming event.
Complete all electrical circuit inspections and engine repairs as described
If a vehicle has been brought in with GPCM concerns or DTC P064C the GPCM battery positive cable will need to be inspected. Inspect for loose connections at the GPCM Connector (squeeze type terminal number C1 or X1) and at the power source/mega fuse. If the squeeze type terminal is damaged, the complete cable would need replaced. If the GPCM terminal is damaged, the GPCM would need replaced. Retorque loose mega fuse/power source connections using current SI specifications. The ignition voltage supply from the under hood fuse block must be consistent
GPCM stands for glow plug control module
basically if all connections look good, one of two issues, replacing the battery cable that attachs to the GPCM.