Fuel

[samwiessner3]

So I have a weird issue and I can find similar ones but I haven't been able to find someone with the exact same one.
98 tj 4.0 ax15
New fuel pump about 5000 miles ago. I can fill my tank up or put $20 in and half the time it'll read half a tank. 30 seconds later it could read full or the light could be on and it could read empty. Its a coin toss as to how much fuel l actually have.

 

[CharlesHS]

Check the fuel pump harness connector to see if the terminals are oxidized or the connector isn't snapped together properly. Otherwise the sending unit attached to the fuel pump may be having problems.

 

[Mudflat]

I had an old Subaru wagon way back in the early 80s that would do, essentially, the same thing. ‘Never could figure out exactly what was happening & back then I didn’t have the money or the time to dive in & fix it. Ultimately, I just figured out about how far the car would go on a tank of gas, reset the trip at every fill up & watched the miles giving myself plenty of wiggle room so that I wouldn’t run out of gas.
I know this isn’t the solution you’re looking for, but until you figure this out it will work for you & it doesn’t really take very long to get used to it & feel comfortable about your fuel status.

 

[TWiG01]

I had the same issue with a Bronco and it ended up being a bad ground. I’d start by chasing wires, connections and grounds.

 

[glowell222]

So I have a weird issue and I can find similar ones but I haven't been able to find someone with the exact same one.
98 tj 4.0 ax15
New fuel pump about 5000 miles ago. I can fill my tank up or put $20 in and half the time it'll read half a tank. 30 seconds later it could read full or the light could be on and it could read empty. Its a coin toss as to how much fuel l actually have.

Have the same issue. After a fill up, I have an accurate reading above 3/4 or below 1/4 of a tank. In between 1/4 and 3/4, it's a guess. It's a known issue, and it's related to the sending unit inside the tank, after checking and cleaning all of your grounds and connections.