Fuel Pump...No Start

[texplorer1994]

I replaced my fuel pump AGAIN after a year and a half with the old one. Again, I am having the same problems as before. I do not hear the comforting hum of the fuel pump when I turn the key and the engine does not start. This is a sporadic problem and that makes it that much harder to test. The clips on the wire harness connection near the pump are broken, but it always seems to be a good connection. I put dielectric grease in the connection, but I am still have problems.

Is the problem the connection?

Is the problem the wire? ---too old and needs to be replaced

Is the problem the control unit on the frame rail near the fuel filter and what is that unit?

PLEASE HELP!!!

 

[aldive]

Have you checked the fuel pressure?

 

[Jason_25]

I'm thinking it's the fuel pump relay. Do a search on it and come up with what you find.

 

[Limited Ex]

The SAME thing happened to me today after I had gotten it out of the shop for AC work. It died on my going down the road, and would not turn over for nothing. Same symptoms also; cannot hear the pump hum on start up, cranks but does not start up. But I am on the original fuel pump, and I checked the relay by pulling the fuel pump relay and putting another one in, but no avail. So tomorrow I get to have it worked on AGAIN, and I will let you know what I come up with :fire:

 

[Limited Ex]

fuel pump went, yay

 

[texplorer1994]

STILL I am haunted

Reference: 1994 Explorer
I purchased a relay on Friday and replaced my old one. STILL the problem persists. If I do test the pressure (engine side of filter or where?) what will this tell me??????
Good pressure-everything is fine and it is electrical like I am thinking
Moderate pressure-fuel pump that I replaced was bad
No pressure- fuel pump is worthless or the pump is not getting current..........which is the sporadic problem I think I am having.

So...I guess I need to always carry the volt-meter and be ready to test...if the current is there with no humm it is a bad connection or a problem with the pump OR................. WHAT!?!?!?!?!?


IF it is not the connection or the pump what else could it be and what is that computer looking box near the fuel filter?

Thank you everyone for the previous help and I appreciate any further help.

 

[Todd W]

fuel pressure

the fuel pressure should be about 45 psi with the key on and 35 with the engine running. in run mode it could be up to 5 psi less than spec but no more.
the first thing i would do is fix the connections. replace the old stuff with some new connectors. if nothing else you've eliminated that possible culprit.
there is a shrader valve on the fuel rail to test fuel pressure that is where to test. looks like a tire valve stem (little black cap and all) you will need a high pressure gauge with the special valve connection to do this test. the problem could also be the fuel pressure regulator. this is a small box on the fuel line where the fuel rail comes out. there is a vacume line hooked to it. it might be pooched and not letting any fuel to the injectors. good luck todd

 

[Guy Groves]

I knowe this sounds like a stretch ....
I seem to remember some other folks having similar fuel pump problems, especially after having AC work done on their car.

It turned out to be the fuel pump safety switch (Inertia switch), located below the glove box on the foot well. It turned out that there were certain conditions this switch became activated and needed to be reset.

 

[Limited Ex]

Welllll..... my inertia switch is fine, checked that today after we got the fuel pump removed, which worked when it was hooked straight to a battery, but also come to find out the EEC (electronic emissions control) fuse under the hood was blown, so that was replaced but since then I have not heard anything. So I have no idea at this point

 

[config]

Happened to me.

Had the same exact symptom. Dealer replaced the fuel pump and a few months later the problem appeared again. Turned out to be Power distribution box. I never really fixed it but I now know to wiggle the fuel relay a few times (with the ignition on) until I hear the fuel pump come on. DO a search on FUel pump and it should explain it in detail. Hope this fixes your problem.

 

[Limited Ex]

Okay, mine got fixed! It was not the fuel pump after all, when the guys who fixed the AC put my intake back on, they pushed some wires against the exhaust manifold which melted and shorted my EEC fuse. So, fix the wires, replace the fuse and it was fixed.