electrical issue

[Artie in Miami]

While changing my trailer light plug, my screwdriver touched the ground pin and the right turn pin (inside the plug) the engine happened to be running so I could identify the wires for stop, turn etc...the instant the screwdriver shorted those two pins, the engine died (no sputter...just stopped). After I finished the wiring, I started the engine and when I put it in reverse (with foot on the brake) the engine died. I disconnected all trailer plug wires, started the engine and was able to put it in reverse without engine dying. Took truck to the store and when I tried to put the signal light on, engine died. When key is on without engine running, signal lights do not work. This has me scratching my head ! When it dies, it will not start right back up...cranks, but won't start...if I let it sit for a few hours, it will start again. 1990 GMC Suburban TBI 350. Bought the truck in 2000 and this is the first real problem in 20 yrs ! I also have a 1986 Suburban 350 4 bbl with towing rear end...I was going to change the trailer plug on that also...but I think I will not !

[cadillac_al]

You wouldn't think the tail light wires would affect the ECM but who knows. If it doesn't run it should set a ses code. I doubt that this would happen on the 86 with no ECM.

[pound41]

This is totally random and off point but. I have a 2003 GMC 2500HD 8.1L that I bought new
Only owned it a month It was cold went into reduced engine power on the 2nd time I started it that day. It would only do when it was cold and 2nd start of the day and never would quit while running. for 16 years I never touched it. Changed the plug at the throttle body and everything went to hell. Would quick while running. had everything replaced same results. Ordered a new harness for the throttle system. Guy who was going to put it on for me is a mechanic at a large military base. I was telling him what was done to it etc and he was telling me that they had several trucks that went in REP and the cause was a ground on a taillight He said fix that ground and the truck was good until the ground went bad again. So who knows. Trace those Tail light wires and see if anything shows.

[87max]

check your grounds bizarre things happen when they go.