92 explorer fuel pump

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Oct 25, 2001 | 03:46 PM

92Roger

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92 explorer fuel pump

I get the sound of the fuel pump running after the engine has been shut off. It usually runs for 1-2 seconds within 5 a minute of the engine being shut off. I also can tap near the fuse box under the hood and make the pump run. A moderate tap seems to activate the fuel pump. Each tap will produce a pump running sound that lasts about 2 seconds.

Can anyone suggest the cause of this and if it presents a current or potential future problem?

Where is the fuel pump relay located? Is there a pressure sensor that activates the fuel pump when pressure falls belowa certain level?

Oct 25, 2001 | 11:37 PM

PAUL_2

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92 explorer fuel pump

It sounds like the fuel pump relay is the problem . Its located under the the engine fuse / relay block . There will be 3 relays , the one closet to the front of the vehicle is the fuel pump relay .

Aug 20, 2002 | 03:14 PM

dawnkyle

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92 explorer fuel pump

>I have the exact same problem with my '92. The bad news is after about 3 months of hearing that fuel pump run after the key was shut off, I started having trouble with starting it after it sat over a weekend. It has been in and out of the shop 3 times. The relay was replaced and the wiring checked. After each "check-up" I wouldn't hear the noise for a few days and then the cycle would start all over.

Does anyone have advice on what to try next?

Aug 21, 2002 | 06:20 AM

adbradley

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92 explorer fuel pump

Did you get your battery checked? Mine did the exact same thing and it was the relay. It kept draining my battery and would destroy the cells in a matter of weeks. I went thru 2 batteries before I isolated the problem and changed out the relay. You might have a short or an open circuit somewhere between the relay and the fuel pump, but probably not since your fuel pump probably wouldn't work. You probably got a bad relay and for $5 bucks, you can't expect much. I would get a new relay from Ford and see if that cures your problem. Mine has been going strong for a year now after replacement...

Aug 22, 2002 | 12:51 AM

92Roger

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92 explorer fuel pump

Interesting that you mentioned hard starting after the truck had been setting for a while. Mine has the same symptom. It usually starts on the second try. It may stumble a bit the first 2-5 seconds but then runs fine. I suspect the fuel system is loosing pressure over time andthe fuel pump doesn't get the system properly pressurized. When you first turn the key on the pump is susposed to run to pressurize the system. Perhaps turning the key on and off without starting the truck might help. I don't have a convient way to check the fuel system pressure. Does anyone have a way that doesn't require special equipment?

Aug 22, 2002 | 05:52 AM

adbradley

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92 explorer fuel pump

Only way to check fuel pressure is with a gauge. You can probably borrow one from Autozone. Might be the check valve in your fuel pump is bad and is allowing the fuel to drain back into your tank instead of creating pressure in the fuel rail. If you can turn the key on a couple times and hear the pump whizz and then it starts, it's probably the check valve...

Aug 25, 2002 | 02:50 PM

jwtb1

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From: San Antonio Bexar

92 explorer fuel pump

My 93 had a fuel pump relay that sometimes would not make contact and the car would not start. The relay is located in the power distribution panel under the hood on the passanger side an is clearly labeled. I found that the "WOT AC" relay (located just above it) is the exact same type, but uses the opposite contacts. Normally open for the fuel pump and normally closed for the AC. That means that the faulty contact in the fuel pump relay would not be used in the AC slot, so I just swapped them. Both circuits now work fine. The AC relay is provided to allow the PCM to kill the AC clutch in the event of overtemp. This trick, however, would not work as well for your situation because, rather than a single faulty contact, you have a flakey relay wiper with intermittant operation that affects both contacts. Swapping relays would shift the problem to your AC clutch. Anyway, the 93 AC relay makes a good emergency spare for the fuel pump relay in the event it fails to turn on some day.