Fuel pump woes!

[A.J.]

As the title states, I am new and thanks for taking the time to read this. I recently had my fuel pump quit, replaced with new one, no power going to the pump. Checked the inertia switch and replaced the relay...

The only thing I can think of is that the computer went bad, when my 94 Exp died the Tach went a little hay wire by moving fully across from 0 to max then back to zero... Anyone have a problem like this and found the culprit?

 

[Sams01XplrSprt]

welcome aj

 

[A.J.]

Thanks for the welcome! I am still having problems with the pump and when I go into other sections of the forum to post up my question in a new thread it states that all I can do is edit my own posts, nothing else is allowed. I get into my thread here and it says the only thing I am not allowed to do is post attachments. SO... Can anyone please help me with my problem? This may be electrical and I need some assistance on what is the norm for this vehicle. I do not know much about electrical but had a friend here test the relays and from what he knows, a Cheby guy, it seems to be ok to him. Any input?

 

[BrooklynBay]

Welcome to this forum! I've moved your thread to the stock 91-94 section. Do you see your check engine light turn on when you turn the key?

 

[MrShorty]

A bad computer is probably the last thing I would think of.

The pump isn't getting power. I don't know a better way to tell you how to diagnose this other than to suggest you get a wiring diagram and a voltmeter. Work your way down the fuel pump circuit until you find the voltage drop. That will be where the problem is.

Have you checked fuses (fuel pump and EEC)?

 

[A.J.]

Thanks guys for your replies, and thanks for moving my thread to the proper location. I just arrived at my TDY location for the next week, I will check the light when I get back and will also start chasing the wire, not looking forward to that since the wire is well covered by the radiator and all kinds of other parts! Thanks again, will report back next weekend!

 

[MrShorty]

My advice, before trying to trace every inch of wire would be to locate some convenient access points, and test for power at those points. Then you can isolate which connectors the break is at/between, and you only have to trace the bad wire.

Examples of good access points to check voltage: fuse, relay, inertia switch, tank connector (on my '92 it's in the driver's frame rail, just above the rear axle, near the spare tire). Once you determine which of these points has/doesn't have power, then you can isolate the fault.

 

[A.J.]

Good idea, I do know there is no power at the tank connector so at least I know that much. I plan on starting directly under the fuse box/relay box and going from there. Thanks again for the easy start idea!

 

[Opera House]

There were a number of relay failures. If I remember, the relays are inconveniently located under the fuses. This should set an engine code. Remember that the relay only turns on for about 10 seconds untill the engine starts. This can make troubleshooting tedious with having someone turn on and off the key while you diagnose. There is a place you can insert a jumper to keep the relay on. Best thing to try is switching relays.

 

[A.J.]

Where exactly is the relay? Under which fuse? If I am not mistaken, there is two fuse boxes, on in the engine bay and one under the dash.

Side note, have not taken much time to diagnos since I recently bought a 74 Scout II but I do need to get this thing running...

Thanks guys for your warm welcomes and for giving me advice!!

 

[MrShorty]

On my '92, you have to lift out the whole housing with the fuses to get at the relays underneath.

 

[ol_ben]

My 92 sport has seemed to develop a fuel delivery problem.
I checked the fuse - it's good, I checked the inertia switch - it appeared good.
I tried to find the relays with no luck. I took out the fuse holder under the hood and took everything apart that was under the fuses, no relays. I opened up the case that holds the fuses I only found only electrical connectors.

Where the heck are the relays?

I had replaced the fuel pump about a month ago. I can't imagine it would fail so soon. I suppose I should check the fuel pump plug connection on the frame rail, but would still like to check the fuel relay.

Anybody have a clue where the relays are?

Thanks,
ben

 

[Tbars4]

...This is where to find the 91-92 fuel pump Relays under the Power Distribution Box...
http://www.explorerforum.com/forums/showthread.php?t=208097

...The 93-94 fuel pump relay is different as in, the 93-94's have the power distribution box on the drivers side and the Relays are located Inside the box...

 

[doonze]

...This is where to find the 91-92 fuel pump Relays under the Power Distribution Box...
http://www.explorerforum.com/forums/showthread.php?t=208097

...The 93-94 fuel pump relay is different as in, the 93-94's have the power distribution box on the drivers side and the Relays are located Inside the box...

Ummm... Pretty sure the power dist box in on the Passenger side on the 93, at least mine is..... and right behind it is the OBD connector. It right up from the battery, next to the air box...

EDIT: Oh, and yeah, the relays are right there inside it!

 

[ol_ben]

Thanks for the link Tbars.

I had actually had the them in my hand but did not realize the relays were imedded in the connectors. I will tackle this tomorrow.

The link is proof that a 'picture is worth 1,000 words'

Thanks,
Ben

 

[Tbars4]

...Doonze, what is the born on date of your X???

..ol ben, I just change one of my other Relays this morning...Just be sure to disconnect your battery cables before you do this...

 

[doonze]

...Doonze, what is the born on date of your X???

8/93 I think, let me go check.

Yep...

Here's the date

Here's My box location...

And here is the Relays...

 

[Tbars4]

...It looks like yours was built just before or during the move on the 93's...:scratch:

...I wish my X's relays were like that...

 

[ol_ben]

My '93 has the relays with the fuse box and they are easily located and removable to test or replace.

I had to replace both the fuel pump relay and the AC relay on the '93 (they are both the same, so it easy to swap one for the other to test. Fortunately both went out at different times.)

For my '92 I originally was hoping the relays were like the '93.
But now that I been educated from the knowledgable folks at this forum, I now have the suspect relay in my hand (and yes, I did disconnect the battery before removing it.)

Now my question is how to test it - or should I just go get one?

Thanks,
Ben

 

[Tbars4]

...For relay info, this is a good place to start...
http://www.the12volt.com/relays/relays.asp

...I myself would just go buy a new one for about 15 bucks, to rule it out of the equation and to know it will not be a problem in the future..