I have a 1988 Dodge dakota v6. It has had some modifying done to it such as a 318 being placed in it and a bit of wire splucing but my main issue now are the gauges. My heat, seat belt, battery power, and oil gauge work but the gas hand and speedometer do not. The speedometer is an easy fix but the gas hand is a bit more complicated. This is what I have done so far:

I have switched out the whole sending unit, no change.

Switched out the old and new sending units with old and new gas tank arms, no change.

By passed the 5 prong connector going to the unit and it had no effect.

I seen there was a alot of grease inside the connecter cleaned that out with a wire brush and got better results. the gauge stayed accurate for about ten tests. It kinda shifted to where it was 90 percent accurate, empty was a tad before E and full was a tad after F and with me being a perfection i went and messed with that and it went back to its original issue of staying in the middle then i got it to register on full but it stops responding right above the half way mark..

another huge issue is tracking the wires. The color scheme changes between 3 and 6 times.. it starts as green, light green, and yellow in the fuel sender, comes out of the 5 prong plug as black/white, purple/ blue, and something else, goes to the fire wall, goes to the multi connecter that had grease in it. from there two of the wires stay the same but the blue / pink one turns baby blue, goes into a huge wiring harness, then goes into some type of multiconnecter on the fire wall which looks good internally then from there i can no longer trace the wires. i seen 3 wires matching the original wires from the sending unit going into the back of the gauge cluster but now im not sure if that means im back on the right track since it changes colors so much..

My question is which all the metal components inside the arm looking good and with me getting it to work about ten times how much more do i need to bypass to get a direct connection from gas arm to gas gauge? Does anybody know the wiring schematics for this 1988 dodge dakota? I cant find the guide anywhere online or at the stores or library and thats a fact.

I'm thinking i can just bypass everything and get a straight line from the gauge to the arm unit but i dont know if anything specials happens to the wire before it reaches the gauge other then going thru these connecters which look pretty basic.

 

Try grounding it better. Take a piece of wire and attach it to the frame on bare metal. Attach the other end to the sending unit with a very small screw type hose clamp. Put it on the metal tube coming out of the sending unit.

 

do what eric suggested. That should fix it since its such a simple set up.