Glow plugs keep failing
Hello all. Thanks in advance for any replies.
I have a 2006 2500HD LBZ motor. I had to let my wife drive it about a month ago unfortunately. Of course when I get back into it the check engine light is on. I have an edge tuner, so I pull up P0675 glow plug number 5. No big deal, I have extras, get home and swap it out. Truck works fine for following two days, then I go to start it, and glow plug light won't shut off. I wait prob 5-10 seconds and check engine light flashes and comes back on. Pull up the code and once again P0675. My first thought is the glowplug had been sitting for years, maybe it had just got banged around in my tool box. I order a set of new ones. Before they get here, and while I was still driving the truck, I pulled the code again one day and I am getting P0678 now too. New glowplugs come, I swap out number 5 and 8. Truck cooled off for a few hours and I went out to test it. Light shut off like normal and started right up. Works fine for a few days, then another cold start, glow plug light doesn't shut off. Engine light on and code is saying p0675 and p0678 again. Obviously something is causing them too fail. Where do I start? follow the glowplug wires to the relay and replace those? Where and how do I check the controlling unit for the glowplugs? Thanks again.
Oh and each time I swapped them, the bad ones had max resistance reading on the ohm meter. New ones had .8-.9.
Last edited by KA4993; 10-23-2014 at 02:42 PM.