Hey guys! This is my first post to the forum; however, I've read many threads as I've been going though my jeep adventure over the past 2 years. Just a quick background, I have a 1996 Cherokee Country with 215,000 miles. I've replaced all the floor boards, rockers, and some parts of the unibody and completely rebuilt the front suspension. In addition, I've also replaced the water pump and fuel tank and pump within the past 6 months.

So, here's the problem:

Beginning a few months, I began to have intermittent problems starting my Jeep. Whenever it wouldn't start, my fuel gauge would be at empty with the low fuel light on even though it had gas. Seemingly randomly, the gas gauge will sometimes return to its normal reading and then will start immediately.

Here's what I've done so far:

After reading through some similar posts on the forum, it seemed as if it could be a problem with the Crank Position Sensor (CPS). I replaced the CPS but it didn't seem to make any difference. After, I replaced the fuel pump relay and thought I had solved the problem; however, it began to give me issues again shortly after.

One interesting thing I've noticed is that if I open and then slam the hood shut, the fuel gauge will indicate the proper fuel level for a moment before dropping back to empty. If I time it right, I can normally start it for the short amount of time that the fuel gauge reads the proper level. Once the car is started it doesn't give me any issues.

It doesn't have any spark when it won't start either.

Could it possibly have something to do with the automatic shut-off circuitry?

Any ideas?

Thanks to everyone!

 

Not sure about the gauge but the cam shaft position sensor also causes no spark. It is the plate under the distributor cap. I think it is also called the ignition pick up. But if slamming the door gets it started probably a short some where.

 

Bad ground seems like a strong possibility.

 

Is the voltage gauge working?

 

My guess is a bad round to the pump, but I don't know the wiring on these to be of any more help.

Someone mentioned a short; it's not a short.

 

Check your grounds in the engine compartment, battery cable and behind the driver's side trim panel in the trunk.

Inspect your wiring going to the pump and CPS wiring.

When you say for the past few months this has happened, and that you replaced the tank and pump 6 months ago, how close to the pump replacement did this behavior start happening? In other words, was it very close, like a few days or a week, or did it run perfectly for 3 months and then this problem started?

 

When I say "check your grounds" I mean take the bolt off, clean the contact surfaces really well, so you have shiny metal on metal contact. Tighten the ground wires nice and tight, make sure the battery cables are tight, ground from battery to chassis is clean and tight.
You likely have something loose if slamming the hood impacts the behavior.

 

The fuel pump and the fuel gauge are both in the same assembly. If they both start and stop working together I would be looking at the schematics to see a common power or ground and go from there with a VOM.

 

http://cruiser54.com/?p=249

 

I couldn't remember where the ground connection is. The post from freegdr is where you want to look first. Also make sure the wires going to the pump are good.