I just bought this truck and the fuel gauge was not reading properly when I got it. It is a 2001 extended cab 4x4. I figured that it had to be the fuel sender so I put in a new one and it did not work. It worked before I put it in the tank because I moved it up and down and the gauge moved with it. The next morning when I went to work, it showed 1/4 tank which was right. When I left to to home from work it showed 1/4 then started to rise all the way to 3/4 before I got home (20 min). When I got home I killed it and let it sit for a while, then it went to 1/2 tank. I figure that it is probably a short somewhere, but do any of you have any thoughts where I should start?

 

Ok, I ran the codes and this is what showed up. PCU-0463 and ECU-1693. Both said the same thing-Fuel level sending volts too high. Any ideas?

I am new to this forum and hope that I posted this in the right section. This is really a great site.

 

If it worked by hand, and now doesn't work when you put it in the tank I would have to question if you indexed the fuel module properly. Perhaps the float is being obstructed.

 

What do you mean by indexing the fuel module properly? There was only one way to reinstall it and the fuel lines line up. The only other thing that I can think of is the float rod being too long. I did not compare it to the original one, I just put it in there.

 

I just replaced mine a few weeks ago and the sending units float rods were the same length on mine. I would agree with you that it might be a bad ground somewhere.

 

I just noticed something that might help out. When the truck is sitting idling, it works. As you pick up speed, the gauge goes towards full. When you slow the rpms it slowly goes to the right spot. The previous owner had an aftermarket alarm system installed. Could this have anything to do with it?

 

I would doubt the alarm system would affect the fuel guage. I would concentrate my checks on the wiring. The ground could cause it and if the locking tab on the plug at the sending unit broke, the plug may be loose causing your problem.