96 fuel guage after ls swap?

[craig98]

is it possible for me to get the factory fuel guage to work after doing the ls swap. I know when it had the 5.7 in it the fuel level was calculated through the ECU. I have deleted the factory computer and just have the ls computer in it. any help would be greatly appreciated I really don't want to run a auto meter fuel guage if I can help it.

 

[Lextech]

The fuel gauge does not get its info from the PCM on a 96 or 97 truck. The 98 and up trucks have the fuel gauge info coming from the PCM.

Jeff

 

[craig98]

Oh didn't know that. Is there anyway to wire it up. My fuel guage sisn't even reading after I did the swap.

 

[Shaun]

i had this same problem. coming from the fire wall on the driver side on mine (1990) theres 3 wires going to the fuel pump/fuel sender. Black/white stripe is the ground, purple is the fuel sender wire to the guage, and the gray is the power supply. after tapping in my fuel pump relay to the gray wire, my guage didnt work. i snipped the black and white wire, and put a hoop connector on it, and grounded itnear one of the bolts for the pedal assembly. works fine now. hope that helps.

 

[craig98]

I figured it out fairly quickly when I was finishing up the wiring I didn't have the fuel pump harness grounds. Hooked the ground up and it works flawlessly. How is your truck running by the way Shaun I'm interested to hear how it does.

 

[Shaun]

good man. i posted a link in the "CHRISTMAS MIRACLE'' thread. theres a short video of startup, and theres a driving video. the driving video sucks, but you get the idea.

 

[99kon]

I just finished the swap in my 99 tahoe and fuel gauge reads passed full like at the 3 o'clock position.
When I first started it up it read fine, now its not. Checked black wire to PCM and it is there. Any ideas? All the grounds from the harness are bolted to a good ground.

 

[craig98]

I'm not sure to be honest the problem I had with mine was the ground wire on the fuel sending harness. I didn't have it grounded. What year is your Tahoe? In this thread lextech said that 98-up gmt's have the fuel gauge information ran through the PCM. Maybe the ls computer has a different ohm range from the factory PCM.

 

[99kon]

It's a 99
I did check that the pin was in the correct place. It is a black wire. I guess i just have to trace it.
What color was the wire on the harness on your truck?

 

[craig98]

It was ether a solid black or black with a white tracer. Il be at my shop tonight to finish up the air ride on it. Il look at the harness and let you know.