Bad ground? Please help!
I have a 93 Chevy Silverado 1500
4x4 ext cab, short box with the 5.7l
motor n auto tranny. My problem is
this, since I had my motor replaced I
have had weird electrical things
going on. Such as when I turn my
turn signals on, my radio cuts out for
a second, my speedometer and tach
dance when they blink, and my
battery gauge drops. The battery
gauge never reads at 14, maybe at
10. I can't use my headlights, and
radio at the same time, I can't use
my windshield wipers and radio at
the same time. It's almost like there
is not enough power. But my truck
starts and runs just fine tho. Every
time I hit the brake or anything that
uses power i can see all the gauges
react. Even my fuel gauge. Any
ideas??? I can't take the truck back
to where the motor was done as that
shop would only charge me a arm
and leg. They bent me over for the
motor replacement when I supplied
the rebuilt motor to put in it.
Did you check and make sure all the ground straps were re- installed? Check and clean your battery terminals and cable ends and have the alternator checked too.
I'm not sure when Chevy began using ECU's but you may find this usefull if you have one ... ECU's utilize isolated grounds for data so be aware that there are conditions when the ground is controlled rather than +12. ... I know that O2 sensors use a controlled ground in able to sense the heater current as an example. Notice at the bottom they reference the ground distribution schematics
I just looked at my motor and it did not have any grounds. Is there 1 to the engine block to firewall and 1 from the battery to the frame?
Yes, your negative battery cable should be grounded to block and body, and multiple other grounds should tie frame body and engine together, otherwise a host of electrical problems can ensue. Best bet is to get wiring schematics/diagrams to help pinpoint grounding points, a service manual although expensive would be well worth the investment.
I also found that sometimes, the positive cable is too long and will bump against metal causing a short if it happens to bump your exhaust or rub itself down to the wire....I run into this all the time..I go from a start to a no start weird electrical wig out issue....found my positive was rubbing the exhaust and the inner fender well
I have a 93 GM 3500 Box Truck, it is a van chassis. Fuel pump quit working, now headlights aren't. Battery has 13.1v in it. Cranks over and starts with ether, but no gas. I thought fuel pump was out so I bought a new one but haven't tackled dropping the tank. Watched a youtube video about weak battery causing fuel pump to not work. So I started checking. I put in a new fuel pump relay. It has power to it. I am thinking I have bad ground. Fuel pump went in and out over a days time then just stopped. How do I locate the ground straps for frame and body? Wiring diagram online? Anyone have a link? It has a v6 engine, like a 265 or something.
I have a 97 Chevy 1500 series I have no power no gas no spark no gas turntable turntable turntable no spark no gas I checked my circuit board my fuse the ground light works but when I go to number 85 doesn't come on can you please help me desperate need
To the original poster... hope you fixed your issue but if not, there is a ground with a ring terminal and a screw under the dash on the driver's side right behind the hood latch pull... that's where your problem is i would almost guarantee it.
to the guy with the fuel pump issue, I had a truck once that the whole truck lost ground between the frame and body, could self power pump with a battery, and truck would run, plug in harness that plug had power, and pump wouldn;t run, ran a ground from frame to fuel pump module, and away it went, been a mechanic all my life and that one had me stumped for quite awhile.
also gmc has a ground on the back of the left head that will cause all sorts of dash problems, have fun, it,s a bastard to reach, and find
