sunny5280

Yesterday my friend purchased a 1999 Grand Cherokee Limited. It's in really nice shape for its age. We had it inspected and there were a few minor things we need to address. One is the fuel gauge which is always reading full. In addition the computer "Miles to empty" reading doesn't change. Does anyone know if there is something simple which I can check? We bought it with the assumption the sending unit will need replaced and factored that into our offer. However we're also hoping it's something simple and can save ourselves a few hundred dollars.

I know the sending until is part of the fuel pump and therefore the entire assembly will need to be replaced. I also have the service manual which tells me what the resistance should be at full and empty. However the service manual assumes the sending unit is out of the fuel tank. Does anyone know if the resistance can be measured easily while it's still in the vehicle? And if it's safe to do so (don't want to be creating sparks around the fuel tank)?

I'll be doing some investigation but thought I would check in here first.

sunny5280

Just to follow up the fuel gauge appears to be working fine now. The fuel information provided by the on board computer appears to be working as well. We hadn't done anything to diagnosis or correct the problem so I can't say what it was. Maybe the sensor was stuck and a new tank of gas corrected it.