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Discussion Starter · #1 ·
just curious about this #2 and #7 injector harness issue, I see where some people claim the connections actually degrade due to them being somewhat exposed to the elements!

Anyone thought about adding some dielectric grease to the connections if/when doing the ice pick fix?

Just curious on the thoughts about that, any cons to it you think???

I just had mine act up on me where it kicked into limp mode and wouldn't go over 2k rpms.. changed thru all the gears fine as long as I was moderate on the pedal but if I hit the gas hard it did nothing at all! So I know it wasn't tranny limp or anything like that. I held the gas at 1/3 trottle from a dead stop and it changed gears everytime at about 1900rpm and I got up to 60+ with no problem!
Anyway I was going in to do the ice pick fix and it appeared that my #7 injector already had the new harness on it! I heated the pick so it would melt thru the connector housing but then noticed it came up thru the pin on the inside.. looks like these pins are not solid but have a small gap or slit running thru them?? Either way I probed the pins a bit and put back together on the #7 injector only and I couldn't make it fail again in the initial test afterwards but we'll see, one 30 minute test ride on and off the gas isn't really enough probably!

Little history mine messed up one time with me two weeks ago so I took it home, tried a couple days later on a short 10 minute ride playing around and no failure.. Got it out Saturday and about 10 minutes in I got down on it to pass a car and it kicked out to limp mode again! No Engine light/codes thrown so I replaced the fuel filter and hit that #7 injector while I was there! Then took it out for a solid 30 minute ride getting on it regularly trying to induce failure but got nothing so we'll see what it does this weekend when I try it out again! I bought this truck almost a year ago with 83k miles on it and only have 89k on it now. I put the bullydog on it when I bought it but have never abused it!

Sorry for the long post but details always make it better! :rockin
 

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I'm a mechanic on the big rigs and I use dielectric grease on EVERY electrical connection that I repair or work with. ECM connections, sensor connections, harnesses...everything. Absolutely no cons to using it. Whenever I clean connections, I always spray the connection with contact cleaner, blow it dry with shop air, ice pick trick to tighten all prongs and then apply a thin film of dielectric grease. If you do get the grease, use the type that comes in a tube (like silicone) not the spray crap.
Doing this will keep your connections free from getting wet or dirty and breaking down/corroding.
Hope this helps! My 2 cents...use it! I think more people would have less issues with connections if they did! Notice, I said "connections".
 

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Quicker Then Brian!
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The limp mode you are seeing is NOT due to the harness problems. It sounds like a fuel limp. If the harness goes out you will be hard pressed to break 25mph and it would sous like your driving a 24v cummins right after a cold start

the grease can help the harness issue a lot of the time the issue is not actually a connection failure but the wire in the sleeve breaking due to the extreme angle it's on coupled with the vibrations of the engine
 

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The limp mode you are seeing is NOT due to the harness problems. It sounds like a fuel limp. If the harness goes out you will be hard pressed to break 25mph and it would sous like your driving a 24v cummins right after a cold start
I SECOND that. Mine happened two weeks ago out of the blue and the noise the engine made sounded like someone threw a roll of quarters in with the pistons. I was scared $hitless.
If your engine isn't making a noise like that, it's NOT the injectos.
 

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new member of the Forum but I visit it frequently for questions I have about my 04 Duramax LLY. I recently began having issues with my #2 injectors as seen by the DTC code and check engine light I was getting. I (what i assume can only be temporarily) fixed the issue by disconnecting and reconnecting the connector almost 20 times, (I did this without removing anything from the area which was a pain.) then I applied a pretty healthy amount of Dielectric Grease and my DTC, and check engine light are gone and the truck runs fine. It could simply be coincidence that they went away when I "Cleaned" the connector by reconnecting it several times, but I think it should be better now. I'm taking it for a 120 mile drive tomorrow and hope it stays golden the whole way. (BTW. the idea of simply reconnecting the injector connector over and over comes straight from the Service Bulletin put out from GM, saying that should "clean" the copper connections enough to get a solid connection given that the issue is not from worn or broken wires in the harness) Thanks for the grease idea though! worked like a champ!
 
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