First this is aggravating. Second I will try to explain as simply and as accurately as possible.
89 XJ 4.0 4WD auto
When I got this jeep it would not start so I figured it out to be fuel pump.
1. Old fuel pump = no start but fuel gauge worked
2. New fuel pump = started it up but fuel gauge didn't work
3. Took out new fuel pump hoping to fix stuck bobber. When I move the bobber up the gauge goes up, when moving down fuel gauge goes down.
4. Put new fuel pump back in and it STARTED THEN CUT OFF. Fuel pump made high pitched hum. Fuel gauge still didn't work
5. Went and got another new fuel pump and it started back up but fuel gauge still doesn't work.
So if I take out pump and move bobber it works but as soon as put back in it goes straight to E and stays. This is getting ridiculous.
Also I'm getting fuel pump assemblies just to let you know. I stupidly threw away original. I should have just gotten the pump. I also poured a little gas in to see if that made it start reading.
If you buy a fuel pump for an 88-90 Jeep XJ and the gas gauge was working then stops after new fuel pump. This is for gas hands stuck on E. not sure if this works for F.
Test to see if sending unit works.
1. Keep fuel pump out of jeep.
2. plug in connector
3. Move float up and down
4. Watch for moving gas hand
5. If it moves the way it should but goes to E when putting into tank.
6. Bend float arm straight and it should fix it.
I guess the float arm just isn't long enough to reach without bending it straight. After bending mine it went straight to a little above 1/4 which is right.