i changed out my 89 cherokee tank and put in a 94 cherokee tank and now the gauge is backwards.. full is empty emty is full.. it is a direct bolt in and you cant put the wiring switch in backwards. what do i do to correct this?

 

My question is the fuel sending unit/pump what, was it for a 94 or an 89? Only reason I ask is the plug might be the same and the wiring might be different between models..So in a sense the sending unit could be sending the signal backwards for your 89..Only thing I could come up with..

 

The sending units operate backwards for Renix Cherokees and HO-era models.

One reads 0 Ohms resistance at empty, the other reads 90 ohms resistance at the sender at empty. I can't remember at this moment which was which. But yes they are operating correctly. They just operate opposite of each other.

 

Mine did that for a year until I added an extra ground to the top where the sending unit and pump go into the tank. Mine is a Renix Jeep BTW.