91 k5 problem

[Chris eckelbarger]

My 91 k5 immediately died after going over a speed bump. I noticed the fuel gauge read way over full when it was down at an ⅛. It would crank but not start. Towed it home and went out this morning and was trying to figure out what went wrong. Had the key in the on position and noticed the fuel gauge went down while I was trying to look for something obvious which I didn't see. Its started up seemed to run fine test drove it with no issues fired right up when I shut it down so I am completely stumped. Went out to go to work and it did it again. Waited a minute or so and started and ran fine to work and home. I'm completely stumped on this if someone could help I'd appreciate the input. Thanks

 

[eric67camino]

When it's doing the overfull fuel guage/no start, will the fuel pump run? It sounds like a bad ground that's getting and intermittent connection.

 

[Chris eckelbarger]

I'm not sure but don't think it is cause it didn't seem to be getting any fuel but wasn't sure if that was normal for the tbi system. Me being half deaf doesn't help cause I honestly never hear the pump running. Can you tell me where the ground for the fuel system is by chance. I would like to check that before I change my fuel pump cause I was leaning towards what your saying or maybe the pump itself was getting ready to completely go out. Thanks for the reply

 

[eric67camino]

I've not been in one in a while, but there should be a connector at the pump. Believe it's got 3 wires. A power wire from the relay, a signal wire for the guage, and a ground wire. I'd make sure the connection isn't corroded first. Then check that there is continuity from the connector to ground on that wire. If that's good, I would see if the power wire is getting 12v.

 

[6872xtc]

The connector for the fuel pump and gauge is inside the left frame rail at the front of the tank. The ground wire for both is there close by as well. Most likely the ground wire or terminal on the frame is poor.

 

[eric67camino]

I forgot to add, if you ohm the ground wire, and its high (more than 0.1-0.2), need to check for the wire being broken inside the insulation. I've seen wires where the copper strands are broken, but the insulation is still intact. The ends of the wire still make contact, sometimes, but a bump may make them loose the connection or make it reconnect.

 

[Chris eckelbarger]

Ok thanks a lot for the replies I'll check things out. It hasn't acted up since that second time so I'm hoping its not the pump.