[CclickLLY]

I've been having trouble with my main wiring harness connector. It knocked out an injector before I realized that the bottom of the connector is melted and the pins are falling out of it. Is it possible to rebuild just the connector end of the harness? or would it be best to just go ahead and buy a whole new wire harness?
thanks for your help!

 

[jake111]

We're talking about the wiring harness to the injectors, right? If so, there are several notorious problems. I haven't heard of one of the injector connectors melting, so that's a new one. Usually, the problem is that over time and with vibration, the metal connectors loosen up and the circuit goes open. The FICM recognizes this and sets a P020x code (x is the cylinder) and then, to get your attention, shuts down 4 cylinders and sets a P2146 or P2149 code.

Usually, the problem shows up on #2 (P0202/P2149) or #7 (P0207/P2146), but it can happen on any of the connectors.

A temporary (or permanent for some) solution is to "ice pick" the connector (or do something similar; I used aluminum foil once). The idea is to re-establish the electrical connection so you can continue down the road.

GM sells connectors (VERY expensive) and there are some very cheap ones on Amazon (I've used these and had great success so far). So, usually, just the connector(s) need to be replaced, not the entire harness.

Another injector harness problem is where it is pulled tight over the alternator bracket near the FICM. It needs to be released, inspected, protected (like wrapped in a cut piece of heater hose), and gently reattached. Otherwise, it wears through the insulation and you get random and weird problems.

 

[CclickLLY]

I'm talking about the main connector for that harness...the one that runs the FICM, Injectors, ect.
What first caused this was a faulty relay for my aftermarket fuel pump. It' burnt to a crisp, knocked out a bunch of fuses. When trying to start the pickup after replacing the relay, there was smoke coming from the main harness connector. Never saw it again....pickup ran fine for a week. Driving down the road, the pickup just loses all power. I knew that I blew the EDU fuse, put new fuse in, blew it right away. Unhook batteries, new fuse, rehook batteries...pickup runs good enough to get me back home (about 2 miles), knocks really bad though...so I think this is when I lost an injector.

Mechanic comes over with computer and checks injectors...yep, injector 6 is bad. Hauled to his shop, replaced injector, still running rough. Search around and finally found that the bottom of the main connector is broke/melted basically falling apart and that the pin for injector 6 isn't making connection. Zip tie it all back together....pickup runs fine for a few days, and now will go into limp mode(truck rattle) every time you move it. Push connector back together and it is fine. I'm scared that if I run it like this, it's gonna knock another injector out. SO, what I need is to know if that connector is rebuildable, or do I have to buy the whole new harness? Thanks for all the help!

 

[Ron Nielson]

ZIP ties have been used for connectors that just won't stay together. Perhaps not the most sophisticated repair, but the price is right and in many conditions it works just fine for many years. Make sure you use quality zip ties, not the dime store kind.