Whats going on everyone? New guy. I wanted to see if I could get some help or suggestions.
I figured I'd just jump out there and get a thread going. Also I'll try to keep it reasonable.

Long story short, I'm experiencing glitches in my Burban and I wanted to see if anyone on earth has experienced the same thing.

[93 gmc burban, 5.7L, base, k2500]

Any time I experience a glitch, it will Always trigger the wipers. Once the glitch has come and stopped, anything electric-related can cause it to freak out, for instance: hitting the brakes, turn signal, radio, headlights, hazards and horn.

When the glitch is Really bad, it will drop the idle and attempt to kill the engine. while doing so, the gauges will flicker and if I have lights on, they will become very dim. It loses power. My acceleration becomes extremely sluggish. The only way to bypass the glitch is to either keep driving while pressing the accelerator pretty hard (if I'm on a highway) or revving the engine while city driving and pressing on the brake. The glitch gradually goes away, starting with not killing the engine, then the lights restore their brightness, then the gauges restore their proper place, and if I'm listening to music the radio will restore its sound.

The glitch basically gives you the impression the alternator and the fuel pump is going out......but its not.

Other than that, when the truck is Kind of glitchy, all it takes is the truck the warm up and I'll hit the blinkers or hit the brake and the windshield wipers will go off once or twice.

One other weird thing: if I hit the horn, it will jump my speedometer up to 100mph (depend on how long I hold it) and it will send my temp gauge to 1000˚ (basically it will do a 180).

Background? I don't know much, other than it being a railroad truck. The front and back seat has a fairly big hole in it in a certain area, cause I was told there was a rat problem at one point in time. I could only assume they got into the dash area. I've had my steering column rebuilt because the first one would cut the truck off completely if you turned it as little as 45˚in either direction. Its possible the guy didn't use 100% all new wiring.


other than that, this truck is smooooth.

Thanks for looking and your help.

Well, considering a possible rodent infestation that chewed who knows what, and a half-assed wiring job by the previous job, we have no IDEA what is going on inside that truck. Right now, your best bet is to start from the power source and recheck every single connection working your way back.

i would start by finding all the chassis grounds and cleaning them to bare metal and reattaching. the ones under the dash, ones that hook the chassis to the frame, ones for the lights, the engine and the battery

Right.
I had a real mechanic take a look, but said he couldn't find anything wrong. I don't think he did much hands-on, just electrical tests. It won't show up with readers and testers.

Me and the mechanic were thinking similarly; of the dash has to come out, then I'd better have some new wires ready because I know plenty of them will be brittle.


I have quite a bit of knowledge and confidence to dive in, but I'd prefer to have some literature beside me if not a much more knowledgeable mechanic.

There are 2 ground wires at the thermostat housing stud. Move them to another spot.

ill have to check that out. if anything, ill sand a new surface.

the mechanic i took it to told me he checked my grounds, other than whats in the dash. I don't think he unscrewed anything, just visual and electrical test.

i don't have a garage, so ill gradually make my way out in this cold MO weather.

I got a chance to do some cleaning up of that ground, and there was another one on my firewall. I'll have to see how that plays out. The one on the thermostat was pretty short, so there wasn't anywhere else to put it without clipping and extending.


But overall, is not like I experience glitches immediately and every time I drive. I went for a drive today, with some stops, and nothing happened. I had on my headlights and radio.



The mechanic I had looked at it wanted me to keep an eye on my alternator, because when I turn on my radio and headlights, turn on my signal, put my heat on medium or full blast, and press the brakes it uses a lot of power to the point it starts moving my battery gauge down to the 10-12 range. It'* usually 14 and some tenths.

that may play a part, because when I was leaving I could see my headlights dimming as the signal was on.

Bad battery cables
Bad battery
Bad alternator. Sometimes they will fail gradually. Meaning they can charge at a high RPM, but can't keep up at a low RPM. Especially with a load on.

Well I put some new cables on cause the old ones were brittle and I converted it to top post.. But the battery is used. And I'll just have to keep an eye on my alternator. It hasn't made any noises yet or shown any dash signals. I don't know if I can say the glitch uses the potentially dying alternator/battery as a stepping stone to freak out, or if that will just be a separate future issue.

the alt sense wire goes through the dash on those to the charge light, all could be issues there.