Fuel pump trouble.

Dustin Yenny

Registered User
Well the title says it all. My car decided to die on Friday leaving it stranded for a few hours. I had thought the car ran out of gas (~1/8 tank) but after adding 3 gallons I realized otherwise. So, I called AAA and had it towed to my house. I swapped in a good pump relay to no avail.

Saturday, I bought a fuel pump from AutoZone since they were open and had it in stock. I dropped the tank and replaced the pump along with the sock and filter. I got the car back together (minus the exhaust), drove it around (~20 miles)....oh man is that thing loud in 4th and 5th gear with no exhaust. The car ran fine for that short trip.

Today I put the exhaust back on and drove around (~10 miles). Once early on in the trip when I floored it and the boost jumped up to around 8psi at say 3000 rpms it cut out (like someone flicked switch really quick) then it was fine for the ride home. I got back in town and stopped at a stop sign, left a little rubber, got about 1/4 mile up the street and it died like it had done on Friday.

As of now I have no fuel pressure at the rail and I switched the relay again to no avail. At first it seemed like the car would catch and want to "try to start" but right now it just cranks. I have yet to unhook the fuel lines at the filter but I figure my new pump is shot after 30 miles.....I just don't understand why after it had run fine the night before if I had bought a defective pump.

Does anyone have any ideas other than dropping everything to replace the pump again? Why would a new pump go go quickly? Could I have something else wrong with the car that is making it eat fuel pumps?

I have checked the fuel pump fuse under the hood and it looks fine, the interia switch is not tripped and I have swapped the relays all to no avail. Prior to these problems I got 5K miles out of the car over the last 2 months. Now that I think of it, the original pump seemed a little loud in the morning until it was warmed up.

Thanks
 
Dustin,
I would do a simple test first.

1. Have you pulled any codes??

2. Have someone turn the key to the run pos. Have the gas tank door open and the cap off. Listen to see if you hear the fuel pump come on for a moment, it should.

3. Check your in line fuel filter, might be plugged up.

4. When cranking your car does the green up shift light come on on the dash. It could be your crank sencor. It might be going bad or shorting out. I'm thinking this is the problem.

5. Just off the wall, try putting your finger in the middle of the crank pully. Is the big bolt in the middle still there???? If it is not you nay have a broken harm. bal.

I realize that 4 and 5 are out there a little way off the problem, but some times problem can cross each other and make it look like something else. It allways worth a look..."look twice and buy once".

Kurt Sr
 
Thanks for the reply. The way the car died the first time I thought for sure it was the crank sensor. The crank bolt is present and the upshift light goes out while cranking. The tach is also registering rpms when I crank it. I'll run the codes. I pushed down on the fuel rail valve and there is absolutely no pressure. I have swapped relays, and reset the inertia switch.

At this point I hate this ******* car, and I'm about ready to call the junkyard. This is *****, a ****** fuel pump should last more than 30 miles.

I'll take ride to the car later and unhook the lines at the filter and see if the pump is moving and gas. I doubt my filter is plugged as its new along with the fuel pump sock.

Does the IRCM have anything to do with the fuel system? I have swapped the green relay by the inertia switch but from my experience with SHOs the IRCM has a relay that controls the pump!
 
I got my handy multimeter out and I am showing about .8V-1V from the Black and Pink/Black wire at the rectangular connector down by the fuel tank. This reading was with the key in the on position. I checked for voltage from the red wire at the inertia switch and it showed about the same. The Black/Yellow wire is showing about 12V.

I hooked my old pump up to +12V and to my suprise it works perfectly. The side says Walbro and it has a Ford part number on it.

My car is still sitting along side the road. They haven't ticketed it or towed it yet. If anyone wants to purchase it cheap, email me: SHOnOFF@surferie.net

I don't understand why the new pump ran for 30 miles then quit. It seems like I have a short or loose wire somewhere. When I dropped the tank to replace the pump it must have bumped the wire(s) enough to make contact. I also don't understand why it waited this long (5K) to show its face.

If I'm only showing 1V at the connector "before" the pump then everything in the tank must be good. The problem must be in the wiring before the fuel pump.

Where is the fuel pump diode???? According to my Haynes manual it is before the fuel pump but it give NO location.

Please help.
 
With your car sitting on the side of the road, it sounds like a rather urgent matter. In that case, if you can't get someone to pull it home with a tow strap, or you can't afford a tow, I'll recommend that you take some wire and bypass the relay, inertia switch and the like and simply hook the fuel pump up directly long enough to get it started and back to your driveway. You're right in that it sounds like its not getting juice. I don't have a wiring diagram handy, so I can't guide you much.

But here's a suggestion. You stated that the inertia switch has +12V going in, but doesn't coming out?? If thats the case, you might be just unplug it and jumper the +12 input to the output.
 
The red wire at the inertia switch is showing about .8-1V in and out via the white wire. The Black/yellow wire at the relay (which appears to be coming from the fusable link in the power distribution box) is getting the full 12V. I'm assuming since the white wire coming from the interia switch is not getting enough voltage it can't trip the relay. However when I unplug the relay and plug it back in I hear a click from somwhere. I'll try to jump the 12V from the black/yellow wire to the pink/black at the relay and see if I'm getting the full voltage to the pump yet.

I have no problem having it towed but I don't want to be doing this every other day in a week. I don't trust this car anymore.
 
Well, the car is home. It still does not run. I have jumped the 12V power from the black/yellow to the pink/black wire at the relay and the pump still does not run. My only guess is a wiring glitch (which I doubt) or the fuel pump diode.

Where is the fuel pump diode?????

Thanks

P.S. car is still for sale.
 
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