A while back I posted a thread about how I was having problems with my fuel gauge not working right on my 88 d100 and we came to the conclusion that it was a bad sending unit so I just recently replaced the fuel pump and it made zero difference the only 2 things I can think it may be is a possible short or with my tank being out of a 91 and my truck is an 88. I had to put that tank in because they don’t make the fuel pumps for the 88s anymore and my tank out of the 88 was cracked so I thought that it would be best I just bump it up a step and get a few years newer (I do not think the ohm resistance is any different on the two, they are both 73-10 if I’m not mistaken). Or could it possibly be the gauge itself on the cluster? Thanks for all the help from the dodge forum team you have helped me out a lot and I highly appreciate that!

 

try grounding the sending unit wire at the pump. should make the gauge go full. also are you sure you used the right wires on the sending unit to hook to the gauge? i know there is 1 extra that i am not sure what is for but i would guess if you use the wrong wires it could cause the gauge not to work.

 

I will try grounding it later but I’m pretty sure the wires are right because they were all the same color wires I believe