'93 Fuel Problem?

Do you have spark?

You never mentioned if the check engine light came on when the car started acting up. There may be a clue or two stored in the ECU. A search or a look through the tech article thread may turn up some helpful information regarding pulling codes from the ECU.

Yes there is a strainer sock attached to the bottom of the fuel pump. Don't get too focused on it being a fuel problem until you actually narrow it down to being one. If you're mind is on the fuel system, you stand a chance of missing the real problem.

The easiest wires to check are the ones on the exhaust side of the motor. Start there, with number 1 and if it has spark, it's a fairly safe bet the rest have spark. If you want to check the other side you can. I haven't seen a coil pack have only one bad terminal before (not to say it couldn't happen, I just haven't seen it). If you have no spark, take the module (located on the front of the intake right behind the alternator) and have it tested at an Auto Zone or some place like that.

I would just check the plug that is easiest to pull out. Remember to floor the gas when you're cranking the engine so the injectors don't fire. At this point, if you're not getting spark, the plugs will be wet. If no fuel, then bone dry.

There is a plastic mesh screen that fits on the bottom of the in-tank fuel pump. If your area or favorite gas station has really nasty gas, then I suppose it's possible for it to get clogged. I pulled one out of my 180k '89GT that had just a few specks on it. If your pump was recently replaced, then the screen probably was also.

If you're not getting spark, then a possibility is the TFI module.

If you're getting spark and for whatever reason the ECU doesn't return any codes, then see if it's getting fuel.

Depending on how soon after the fuel pump ran last before you disconnected the line, it's entirely possible for pressure to remain in the system with the pump off.

Okay, so we've got spark and fuel. Question now is do we have enough?

I'm not sure what you mean when you mention "air going to the engine" when the fuel pump is running. Where is this noise coming from specifically? I'm assuming that the engine is not running when this occurs, is that correct?

I'm kinda at a loss here. I can't think of anything off the top of my head that would be keeping you from running. I'd hate to have you running around chasing wild guesses, but at this point unless someone with a higher Ford IQ chimes in, that may be where we're headed.

Let's look at what all there is in the fuel system and rule out things we already know are good or don't matter.

Fuel - got some... 10% ethanol blend
Fuel pump - works, visually verified
Fuel filter - new
Fuel lines - rubber from tank to pump and from pump to filter. hard line from filter to engine compartment, plastic from hard line to rail.
Fuel pump pulse dampener - ?? That's the canister looking thing on the high pressure side plastic line between the hard line and the fuel rail. I don't know the material used inside so I can't tell you if it's ethanol compatible or not.

Fuel rail - it's there, and doesn't leak, that's all that counts.

Fuel pressure regulator - I wonder about the diaphragm inside, If it were to fail, fuel would be present in the vaccum line that attaches to it. Could be ethanol or just plain old age related. Pull the vacuum line off and see if there's fuel there (it shouldn't be)

You know you have fuel pressure at the filter. Let's see if you have it at the rail too. You know where your fuel lines come into the engine compartment on the driver's side towards the back of the inner fender right? There's two lines there, one is the feeder(high pressure) and is the larger of the two, the other is return back to the tank. Disconnect the return line, and point it into a container in a way that you don't get fuel everywhere, and cycle the pump. You should get something if the fuel is making the trip.

A clean way to do this would be with a fuel pressure test gauge on the schrader valve at the fuel rail, but Not everyone has one and if you're rural, getting one might be a PITA.

I'm going to check a few things on my '91 (same basic deal) and see what I come up with. I'm trying to help as best I can, but I don't know everything. I'm hoping someone jumps in here and impresses us both. -

did you check your vaccume hoses? if you hear leaking air and the engine dosnt want to run or is running bad. that could be the problem. a hose can look fine on the top but have a small tear or hole on the bottom. check all your hoses for dryrotting and holes.

I'm not well-versed in 2.3 N/As, but doesnt the fuel pump run all the time anyway? Or do you mean it runs non-stop even with the engine off?

I was also wondering why you changed the ECU after the overheating. Do you still have the original? If the slow drain and fuel pump problem started after the ECU change, I would suspect it more than anything.....even for your current problem.

Your fuel pump runs constantly whether the key is on or not? A professional did this? I don't think I'd ever take anything there again even if he were the only mechanic in town.

This kinda throws everything we've already discussed out the window. I wish you would have mentioned this sooner. At this point, without being able to physically crawl around and look at what's been done, it's impossible for me to sit here and speculate what might be happening.

Sorry dude.

Rideredder said:

I bought a new one because that is what the mechanic said to do to get the fan running again. Then when I hooked it up and the fuel pump didn't work, he said it might be a bad ECU,

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Rideredder said:

Why would that have anything to do with what is happening now?

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Your "mechanic" had you replace the computer to fix a problem with the electric fan......THEN says you might have a bad ECU.......THEN rigs some wires to make the fuel pump run all the time. You've also had an electrical drain since he worked on the car. Does it sound like he actually did a good job? You don't replace the engine computer to fix the fan. The fan controller is not on the ECU. Also, why would it cost you $200 to have him replace a faulty ECU that he supplied?

At this point, it's anyone's guess what got messed up in the wiring and/or ECU or if it's even the right computer. You said you have fuel, but not if the plugs are wet after cranking. If you have fuel pressure and dry plugs, then your injectors are not opening and that points to a harness fault or ECU failure.