Fuel gauge drops to E while driving then engine dies

fireraz · 10-03-2006, 05:33 PM

I'll be driving down the road and I will watch my fuel gauge. It will drop from full to Empty in 5 seconds or less the low fuel light comes on then the engine dies. I sit for 1 min or 3 hours and it will start back up. It will do this 3 times in one day then not again for a week. Only the fuel gauge moves no other gauges. No check engine light. It sounds elecrical but am stumped where to start.. Any help??

It's a 96 Cherokee Country 4+4

kencaz · 10-03-2006, 06:09 PM

Either your getting an (intermittent) broken electrical connection to the fuel pump, or your fuel pump is about to fail. If you frequently drive with your tank less then a 1/4 full then the pump is overheating and will go out sooner.

If I am near empty I try to fill my tank before the pump heats up to much. The cold fuel hitting the hot pump can lead to failure.

Just a theory but I had the same symtoms on my RX-7 which had a in-tank pump.

KC

**Kornik** · 10-03-2006, 06:13 PM

Check all electrical connections between the fuel pump/fuel level sensor module in the tank and body. As it looks like your fuel level gauge dies at the same time as the fuel pump and that's he only place where those wires go toegether.

erik04wrx · 10-03-2006, 06:14 PM

I would crawl under and check the connection, as long as they have not moved from 92 they are just behind the rear axle next to the filter

fireraz · 10-03-2006, 06:17 PM

The fuel pump shuts off after the fuel gauge hits E

fireraz · 10-03-2006, 06:18 PM

What connection??

erik04wrx · 10-03-2006, 06:20 PM

sorry it is a plug that has, if memory serves, 4 wires I would pull them apart and put in some dialetric (sp?) grease, just as a starting point.

does it happen after wheeling or when raining?

fireraz · 10-03-2006, 06:29 PM

it happens speratically (sp). Rain or shine....

fireraz · 10-03-2006, 09:01 PM

normally when a fuel pump goes out it just goes out. I don't think it's the fuel pump because it's reacting to the fuel gauge saying the tank is empty.

**Kornik** · 10-03-2006, 09:52 PM

Quote:

Originally Posted by fireraz

The fuel pump shuts off after the fuel gauge hits E

I would rather say, that the pumps go off when the gauge starts falling down, but as you have pressure in the system it takes some time to kill the engine? That would confirm preblem with wire harness somewhere between tank and unibody.

fireraz · 10-03-2006, 10:27 PM

Do you know where I can get a wiring diagram so I can know what wires to chase down???

fireraz · 10-04-2006, 10:46 AM

What are the odds it could be the sending unit going bad????

**Kornik** · 10-04-2006, 11:09 AM

Quote:

Originally Posted by fireraz

What are the odds it could be the sending unit going bad????

I'd say zero - if the sending unit goes bad you will loose the fuel gauge readings, but the fuel pump will still work. Same in opposite direction - if fuel pump went wrong the engine would die, but the gauge would show correct fuel level. So for me the only way those things can come together at the same time is when there is something wrong with the wires.

I have just checked the wire diagrams for my 92 XJ and there is one harness with 3 wires going from beneath rear seat to the fuel tank. those wires are: fuel pump, fuel sensor and ground. So I'm betting that you have just ground problem.

**sharpie** · 10-04-2006, 11:48 AM

yea, I have a bad FSU, I can drive over 100 miles when I am below the E. Also, it doesnt drop to E when I am driving, but may do it when I start up. I would check the connection, and then the fuel pump.

What about the filter though, maybe it's clogged up too much?

**Ubie** · 10-04-2006, 12:39 PM

Sometimes if i don't completely tighten my gascap after 20-30miles of driving the fuel gauge will suddendly drop to 'E', fuel light will come one and the engine will cut out. I just tighten the cap and make sure i hear at least 3 clicks, 1 or 2 clicks apparently ain't good enough. After that everything is just hunky-dory.