92 f150 died the other night. I switched tanks and nothing. Fuel pump on each tank wouldn't shut off when I selected them and truck would not start. Towed it home. Next morning turned key on and fuel pump came on few a few seconds and then shut off like normal. Truck started right up and ran for about 20 minutes and died. Same thing. Fuel pumps won't shut off when tank selected and truck won't start. Shot ether and doesn't seem to have spark to start, but didn't verify yet with spark tester. I replaced fuel filter and dumped dry gas in each tank. This morning I went out and fuel pump shuts off like normal. Did not bother starting truck up yet untill I educate myself a little more of what the problem could be. Is there any part that would keep the fuel pumps running even when it gets up to pressure and then not have a spark at the same time? Thanks to all that may have some insight

 

There is another post that just started with the same thing. Start there.

https://www.ford-trucks.com/forums/9...lectrical.html

 

your computer is failing.

 

I second the computer notion. We had a truck doing the same thing at work. If I would give it a little snort of ether(not really advised, but we had to see if we could get it to run any at all) and put a brick gon the pedal to hold it at about 1/2 throttle, it would run poorly, chugging black smoke as if it were a diesel. It was a '90 F-150, 4.9/5-spd, and we tried everything before we got a computer from a salvage yard. We did a regulator, injector leakdown test, checked relays and a new pump. The pump made it a little better, at least bringing the pressure into spec. Because the computer was junk, it let the pump keep running, and burnt it up. The computer doesn't neccesarily have to be out of the same year truck. I got the new/used one out of an '89 that had a '93 date code on it, but the truck had the same specs.

 

Just ran it for a couple of hours. Only changed the fuel filter and put a couple bottles of dry gas in each tank. Could a chunk of Michigan ice have got in the line and it took a couple of tries to get the dry gas to work it's magic? Fuel pump kicks on and shuts off like it should for now when I turn the key on. I'm worried truck will still strand me somewhere. What is official name for computer and where is it located if it gives me any more trouble. I'm worried this will be an intermittent problem. Just glad it's running for now.

 

I just use the generic term ECM, but I'm not sure if that's the correct term for this era of truck or not. Its located behind the kick panel on the drivers side. The connector for the harness is in the engine compatment, and it has a bolt that attaches it to the computer.

 

Ice in the fuel line would have nothing to do with the fuel pumps running all the time. The pumps are on a timer in the computer that runs them for one second when you turn on the key and then again for one second after each PIP pulse.
You do have a bad computer and it will come and go for a while and then it will not start at all.

When the the pumps are running all the time you will have full fuel pressure at the fuel rail but the computer will not be grounding the fuel injectors and or may be holding the SPOUT wire to ground. That is why it will not start when the pumps are running all the time.

The problem with the computer is that it has bad Electrolytic Caps inside and they can heal themselves and then brake down again and stop filtering.

 

Just went out this morning and it started right up......and ran for about 20 minutes and died. Fuel pump running. Thanks for all the information folks. I think I will try replacing the "computer". Subford's explantation has me hook, line, and sinker. If this works, I dub him Ford wizard of the century. Intermittent problems can be frustrating. Nice to have so a huge network of knowledgable people out there helping each other with their truck problems!

 

Ok, how do I get this computer out? I know there are explanations out there. I just need a little more info. I unplugged the harness inside the engine compartment, removed the two nuts on the bolts coming through the firewall. It moves a little now but which way do I pull it out. I hope it pulls out through the engine compartment. Do I need to remove the rubber "boot" around it to slide it out or what? You can't even see it from inside the cab. I hope nothing needs unplugged inside. Trying not to lose my cool and take a hammer to it.

 

The computer needs to come out from inside. It's located behind the kick panel on the driver's side. The kick panel is the piece of plastic, on the left side of the footwell, near the emergency brake pedal. It should pull off with a little finesse. Then, there should be 3 or 4 (can't remember exactly) screws that hold the computer in the cab.

 

not on a 92+.

it is removed from inside the engine compartment.

do an advanced search on cpu removal or computer removal as this has been posted 100s of times.

 

You have to remove the inter fender bolts and push it back a little and pull the computer out between the fender and the inter fender.

Yes you take the rubber "boot" around it off.

 

Yep, I took a deep breath after I sent my last reply and went back out. I figured the boot must come off. This thing is bigger than I thought and you definately need to make a little more room to pull it all the way out past the fender well. How important is the last three letters of the code? Mine is an ATA and the closest one is 70 miles away. There is an APA 20 miles away for the same price (60 bucks). Thanks guys.

 

The last two or three letters are very important.
But you need one from a truck about the same year (F2) with the same engine size and transmission type. The last two or three letters if different could mean it is from a car with an automatic transmission and a different size engine.