Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Hi guys! Please keep in mind I am not a auto tech (certainly haven't been around long either) but I'm trying my best to help a friend out.
Back story.
Buddy has a 98 chevy 3500 plow truck with the 6.5 detroit. never had much for problems but the body was falling apart (gotta love Minnesota roads). He ended up finding a dirt cheap 98 3500 CCLB with a blown up 6.5 in it but the body and frame are super clean. He swapped the engine out between the two trucks. He tried starting it and a big flash and smoke appeared under the hood.... This is where I get involved.
I found that he had a ground strap ran from the engine block to the glow plug solenoid positive post.... We had a good laugh at that. Removed ground strap and installed a new fuseable link that blew by the fuse block. Now the glow plugs are getting power. Tried starting truck and it will hit on two maybe three cylinders and that's it. Once in awhile it will attempt to run but stall out, we gave the engine a little sniff of propane and we can get it to run on propane. No codes (dash gauges aren't working right now anyways), When cranking I found a data pid labeled "CKP MISS" I think it was and during cranking it will jump up to 1 then back down to 0. Thinking the truck was loosing crank signal. Back probed crank sensor an we have the 5 volt square wave that is not dropping out and when the truck attempts to start the signal speeds up. Now I'm not very familar with the Detroit's or Chevrolets in general but I see this injection pump set up is kind of a mix between a mechanical/electrical set up. Under the Snap On guided component testing I found a test for the stepper motor they call it. Testing states to Ohm out pin A to D and B to C should be between 10 to 60 ohms. We tried this test on the motor side and had nothing so we carried out the test on the engine harness side. Pin B and C have 53 ohms, Pin A to D have 4.4k ohms..... I bought a mitchell 1 manual for this and looked at the wiring diagram and seen these wires go straight back to the ECM. My buddy stated that in the back of the cab there was 3 spare ECM's......... He also pulled some programmer off of the engine that was plugged inline with the stepper motor (programmer is not on the engine in the truck now). I checked for continuity to ground on all three wires and nothing. When we unplugged the ECM the 4.4k ohm resistance goes away. We robbed the ECM out of his old plow truck (truck started and ran) carried out the same test and have the same exact readings....... This is where I'm kinda stump. I don't want to trust the Ohm meter and I feel like the guided component test could be wrong as well. Was wondering if someone out there could share some more info or guide us in the right direction because I'm kinda at a loss here. We haven't cracked the injector lines yet but to me it seems like it wants to start and run being that it will hit on two maybe 3 cylinders but after those couple hits it will just keep cranking and cranking. Now thinking about it I never cared to check for crank signal at the ECM but other then that I'm unsure of where to go from here.
