Strange elecrical problem

ruddy · January 30, 2007

I have an intermittent problem with my '96 GMC Sierra with the 5.0 liter engine. Every once in a while after starting the engine, turning on the lights causes it to die. After I switch off the ignition and try again, the engine starts right up again, but sometimes I have to give it gas to keep it going. Is this a throttle position or enrichment issue along with an electrical gremlin, or is it all electrical?

unsolved · January 31, 2007

Well Heres my 2 cents.

I would say that if the check engine light isn't on, the alternator and battery are good and the headlights work without your amp/voltage gauge dropping drasticaly and it only does it when it's cold.... Idles rough when cold = Could be an ignition issue. Plugs, Wires, Cap, Rotor, Coil etc... Or REBUILD TIME.

ruddy · February 5, 2007

The engine is idling when this occurs, so it's not a starting issue. No engine check light, starts right up every time.

ruddy · May 22, 2007

The engine is idling when this occurs, so it's not a starting issue. No engine check light, starts right up every time.

Bump

When I turn the headlights on while driving, it kills everything for a split second and then keeps running. It takes a couple of minutes for the throttle response to get back to normal though. It doesn't always do it either. Everything thing else seems to be fine. I just replaced the alternator, and the battery is good. No engine check light.

My daytime running lights quit going on some time ago, and pulling the fuse for them doesn't affect my problem. If I turn the lights on before I start the truck, everything is OK.

Any ideas?

racerx55 · May 22, 2007

have you checked your battery connections, and all the grounds to inside the truck? since it start i would almost rule out battery terminals but anythings possible.

the charge wire on the alt. maybe..

it sounds like a body ground issue to me, just a guess.

well, my 92 would start, if i hit the brakes it would die for a sec. headlights, same thing. but it always started, ended up being the positive termial was corroded.

ruddy · July 28, 2007

it sounds like a body ground issue to me, just a guess.

That was it! One time the alternator wasn't charging after I started it up. I connected a jumper cable from the negative battery post to a chassis bolt and tried it again. Voila! It was charging again. It kept on charging after I disconnected the cable, but that seemed to be the solution. I ran a 16 gauge wire from the battery negative post to the chassis bolt, and my original problem has been solved.