Have 97 c1500. Put a 2004 5.3 in it.
So far only test it idling but it idled fine and gauges did what they should. But of all things that possibly could go wrong, noticed the fuel gauge is past full, 3 o'clock position and stuck there. I've had truck for few years and no issue before.
I'm guessing it's ground issue but not sure where to even begin to look.
Seem straight forward until I realized the wiring going into the passenger side firewall, is some sort fuel gauge buffer?
Tried following a test procedure but nothing changed and the wording used became more and more unclear as to what they were saying.
I believe the 4 pin square connector under the brake booster is the fuel gauge wiring.
I disconnected it and the fuel pump still worked, so either I was probing the wrong connection or the fuel pump uses different connector.
The 4 pin square connector. I tried jumping wires per instruction and no change. Gray wire was showing 10-12v but what I read said it shoukd be more like 4-5v.
The 4 pin connector had gray wire. Purple/white, black/white and green.
I did ground the blsvk/white wire and the gauge moved like 1/8' once but that's it. Never moved again trying replicate the addition of verses without.
I do understand I could trace wires from the tank but I really feel like it has be related to the obs engine harness. Just not certain where to begin. Trying avoid popping the loom open, spent alot time making the wiring nice and wrapping the loom with fabric tape. Lol
I'm thinking there's a ground issue with the buffer module but not certain how to approach that.
Any input appreciated. I'll keep plugging away as I get a chance to but this has me stumped.
So far only test it idling but it idled fine and gauges did what they should. But of all things that possibly could go wrong, noticed the fuel gauge is past full, 3 o'clock position and stuck there. I've had truck for few years and no issue before.
I'm guessing it's ground issue but not sure where to even begin to look.
Seem straight forward until I realized the wiring going into the passenger side firewall, is some sort fuel gauge buffer?
Tried following a test procedure but nothing changed and the wording used became more and more unclear as to what they were saying.
I believe the 4 pin square connector under the brake booster is the fuel gauge wiring.
I disconnected it and the fuel pump still worked, so either I was probing the wrong connection or the fuel pump uses different connector.
The 4 pin square connector. I tried jumping wires per instruction and no change. Gray wire was showing 10-12v but what I read said it shoukd be more like 4-5v.
The 4 pin connector had gray wire. Purple/white, black/white and green.
I did ground the blsvk/white wire and the gauge moved like 1/8' once but that's it. Never moved again trying replicate the addition of verses without.
I do understand I could trace wires from the tank but I really feel like it has be related to the obs engine harness. Just not certain where to begin. Trying avoid popping the loom open, spent alot time making the wiring nice and wrapping the loom with fabric tape. Lol
I'm thinking there's a ground issue with the buffer module but not certain how to approach that.
Any input appreciated. I'll keep plugging away as I get a chance to but this has me stumped.
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