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Here's the verdict I just did a egr delete and oil cooler in my 6.0 ex I got everything done fired the truck up and it ran like crap threw some INjector codes so I started unplugging injectors to see which one were not firing and when I unplugged cylinder 4 the truck started running better and is firing on all cylinders except 4 when I plug 4 back in it runs on Half the cylinder and like crap again? Ever heard of that what's the fix? Any info helps
Did you try running the truck for some time? You probably have air in the system When I had mine done dealer told me to drive her hard wot for a day. Everything was fine after an hour
Did you try running the truck for some time? You probably have air in the system When I had mine done dealer told me to drive her hard wot for a day. Everything was fine after an hour
Yes it has been running all morning and great until I plug the number 4 cylinder up
Did you get the ground wire back on the intake on the drivers side, very last bolt, or stud under the FICM? Make sure you got all 3 plugs in the FICM plugged in hard till ya hear them click in? No bare wires touching, I just did one last week and it runs good, but I have an exhaust leak at the turbo inlet, must not have mated it right when I tightened the clamp, so i am going to have to play with it again, just running through my head what could have happened to cyl 4. Took me about ten minutes to get the air out. Do you have a scan tool?
Yes it has been running all morning and great until I plug the number 4 cylinder up
Running or running it like you stole it?
Last time I had any work done was all new injectors on one side, I waited for it. When ex came out tech shut her down and came inside the service area to tell me it was all done. I paid thanked him for getting it done so fast and went to start my ex. I noticed it took much longer than usual to start and when it did it was running like crap. He came back out and told me to drive the hell out of it and in my case it worked.
All ground wires are on in the proper spot and with the 4 injector unplugged I get a low voltage code but the truck runs good aside the miss from the 4 cylinder being unplugged with 4 plugged in I get get a high circuit code on 1 4 6 and 7 injectors and runs like crap won't rev up
Injectors 1,4,6, and 7 all share a common connector at the FICM(C1388A). Check very carefully for a bent pin, or chaffed wire in that harness. You have a short in there somewhere.
Have you checked resistance across the coils of #4? Compare them to an adjacent stick, or two for reference. The injector itself could also be the fault. I'd prove it's good before replacing that harness.
A lot of times a chaffed wire can be deduced with a wiggle test of the harness with KOER. Moving things around while running will often times change the running condition, and help lead you to a more specific location to investigate further.
I have tried the wiggle test with no help also pulled apart the harness it self to check for a chafed wires with no luck my ficm is holding 48v but I have been told it could still be bad. the excursion ran perfect before the delete, do see a injector going bad over night.
It happens 6.0's eat injectors, please ohm out the low and high side of the injector and compare it with the one next door, I know it sucks pulling the air filter and hoses out, but to replace a harness, just to have injector 4 dead again will kick your dick worst than testing an injector or pins in the FICM. Yes it does happen injectors go bad and if it's shorted thats why the others dont fire right when you plug 4 in. dont hate yourself later test the injector, 2nd one on the drivers side right!
Electrically, anything goes. It could be the FICM, the harness, or the injector.
You need to work from the injector to the FICM. A resistance measurement across the coils should tell if there's a serious failure in the winding. You can swap the injector with another to see if the problem persists in the same hole(cause: wiring/FICM), or follows the stick(cause:injector). The fact the issue only occurs with injector connected leads me more to it being the problem.
The harness may/may not be the problem, and can be fairly expensive if you're just guessing. To check what you have is a matter of testing the appropriate pins to see if there's an obvious problem with the wiring. Since #4 is the root of the problem, there isn't too much to test except for it's coil supply voltages, and commons.
Last is the FICM. You can send it to get tested, or swap with a known good one. Any year 6.0l PSD FICM will run the engine. You might get a soft code for calibration mismatch, but that will not cause running issues.
Did you pull the injectors out and apart by chance? The wiring on the injector itself could be shorted out on the injector body. Not sure what would happen if the magnets (servos?) were reversed on the injector if you had them apart.