95 gmc 4x4 lots of problems can anyone help on this?

I will start off by saying I have replaced the fuel pump, the fuel filter, egr, throttle body positioning sensor, and have checked fuel pressure and for spark. Now, my problem is when I bought this truck, it was jerking real bad like it wasn't getting any fuel. Thats why I replaced all of the parts, My buddy and I were messing with the round black thing on top of the plentium, we pulled it out and looked down in the hole and noticed there was a harness with 2 elctrical wires red and blue, which look like a squeezable clip. We used a screw drive and pushed on it and it snapped in place and locked like it should be, we tried to start the vehicle and it fired right up and ran good for like 5 days. So I took that black thing back out thinking that I could press the clip back down but it was already down, so I put it back together and fired right up again and ran great for a couple more days. Now, it will only start if I disconnect the battery for a couple of minutes but runs rough. I hope that I am being clear enough on what I am trying to explain, I am tired of getting broke down. Could the clip or the thing the clip clips to be burnt up since I was driving it when the clip wasn't clipped down. Any advice is highly appreciated. Thanks. Help me out before I drive this truck off of a cliff, Please.

Pull the trouble codes.

I am having the same problem, I'm going to check the clip you were talking about and keep an eye on this post, I hope someone has a answer for this problem, By the way my check engine light is NOT on, is yours? Also I'm not sure if these two problems are related but when I turn the key off the motor keeps wanting to try to run for a few seconds, (it dieseling out)

Perhaps the contacts in that little "clip" need to be cleaned. Also make sure the intake baseplate is not loose. If there is an air leak in between it and the black plenum then the engine won't run correctly. A shot of carb cleaner aimed at that seam will be sucked in if there is a leak. Also, make sure the black snorkel that attaches to the top of the intake has a good seal as well.

Any errant air going into the engine and not through the snorkel will cause the MAF (mass air flow) sensors to program the engine to run lean, meaning only enough fuel is being delivered for the air that it senses, not what is getting sucked in through the leaks.

It's only a guess, but it's alot cheaper than tearing the top end down...keepin' it simple. Good luck!