Agt. Orange

Ok so the car was a 97 v6 and conv to a 99 ls1 mostly. I used 2000 engine harness and 99 body harness and now the fuel gauge dont work. I have changed the pcm, gauge cluster and sending unit and doesnt work. Sending unit is 99 pcm is 99. When the tank is full it reads empty and when it hits bout 1/4 full it sometimes goes to full, but only sometimes. I need help on this one since it has been kicking my butt for 2 years now. All wires seem to be hooked up and grounds are good. I think i have read that the wires go from unit to the pcm then to the cluster for whatever reason, could this be an issue on this setup as i need to switch a pin out on the pcm? Or is it a tune problem?

Doc

iTrader: (9)

So, do you have any kind of scantool at your disposal? Something that can read what the pcm is seeing from the sending unit? This valuable info will tell you if you have a wiring problem or software problem.

If your pcm can see data then I would bark up the wiring tree. If your pcm cannot see any information then I would question the tune data... what OS and Cal files are you using? What software?

Doc

krusze2

Have you considered checking the fuel level sensor? after reveiwing the 99 and 00 wiring, all wires and pin locations are the same. and as for the guage itself, it is all sent to the I/P cluster over the serial data line. If you have access to a GM Tech 2, you can test the cluster gauge by doing a guage sweep test. If you have access to a signal generator, you could also test your wiring from the fuel pump module forward.