Hey guys, I recently had my 7.3L serviced for a variety of problems. It was running extremely rough and sputtering oil. My wife took it to a local shop that specializes in diesels, and they performed the following:
- Replaced HPOP and IPR
- Replaced o-rings on all injectors
- Replaced one faulty injector

At the time of service, they claimed to have checked all of the glowplugs, and that they all checked out ok. After we received the truck back, it ran much better, but we kept getting a pending trouble code associated with glow plug #6.

My wife took the truck back into the shop to have them look at it, and again they claimed to have hooked up a scanner and everything checked out ok. The owner of the shop said not to worry, as the code should eventually go away. It eventually turned into a check engine light, which we cleared, and has of course re-occurred again.


Flash forward to this morning, the truck is knocking under cold start. My wife let it idle for a while and the knock went away, which leads me to believe there actually IS an issue with glowplug # 6 or the associated circuits, despite the shop's opinion.

How do I go about troubleshooting this problem?

Is anybody local to Acton (near Santa Clarita) that could help me out? I really don't like the idea of taking it back to the shop to get raped again.

Thanks.