2003 Ford Exp. 5.4L apparent fuel/injector issue

My '03 Ford Ex. turns over and over and over but won’t fire.

Suspected fuel feed issue maybe due to bad/trashy gas but not sure.

Shortly after buying gas from a country station during the recent “gas shortage” scare, my Ford Ex., usually very reliable, just stopped running. At the time it was idling in Park in my driveway as I ran back inside for a moment.

I’m not sure it was bad gas but that’s my best guess at this point. The 5.4L will fire if I disconnect air input line at the air filter and use starter spray. Runs a second. Stops. I can keep it firing with continued shots of starter fluid but I do know not to do that very much for fear if damage to the injectors.

Here’s what I’ve done so far, below, with no positive result do far: (Any pointers on what to try next…much appreciated. I hope to fix this myself if at all possible.
Can’t afford a tow to town OR a shop fee.

  1. Determined that it would fire with starter fluid into the air feeder

  2. Replaced fuel filter

  3. Reset emergency fuel shut off valve.

  4. Opened shraeder valve on fuel rail and depressed needle valve.

At this point, fuel does well up out of the shraeder valve. It does not spray out forcefully as one friend said it should. This may be because I did not depress the needle valve enough. I don’t know. I have read previously about using a fuel line pressure gage at the Shraeder valve, but I don’t have one. I do have a regular air pressure gauge but I assume I need a specialty fuel gage. So at present, I know that has is getting into the fuel rail but I don’t know if it’s at the pressure it needs to be to run the motor. I would assume that if there is gas getting the fuel rail, it must be getting into the injectors enough to at least make motor run some.

Same friend suggests I disconnect fuel feed line where it attaches to the fuel rail, and catch some fuel in a clear container to check for trash/water etc. However, that connection does not appear to me to be a screw on/off junction. I’m afraid to go at it until I know more. I do suspect that there must be some trash or something that’s keeping gas from getting where it needs to go to start the car and keep it running.

Same friend suggested I unscrew one spark to see if gas is getting into the head but I have not tried that yet. Is a little daunting given the whole Ford spark plugs system on this more. Hard to get to. I’m afraid I’ll screw something up. I will try this if need be, but do far, I have not tried it.

Right now, I still suspect the issue is somewhere in the fuel feed, since the motor will fire and keep firing with spray starter fuel.

What do I try next? I’m desperate. Any advice here much appreciated!


One other additional “have done” procedure:

I did put in one bottle of STP fuel additive, plus I added about 4 gallons or so of good high octane fuel into the tank but I have not added any more than that.

I would have drained the fuel tank but I’m told that it’s too hard to get to and do without special gear and procedures.

have to ask… are you sure you pumped gas in and not something else. how much did you put in? it seems this happened right after the gas station. could of picked up a lot of junk from the bottom of gas station fuel tank if they were really low and did not have there filters on.

I tend to think this is not gas related and more a coincidence matter. At 18 years of age things start breaking down; and quite often long before 18.

What I would do is remove the fuel pump relay in the underhood fuse/relay box. There should be 2 terminals marked 30 and 87. Thirty should be hot all of the time. Run a short jumper wire from 30 in the relay box to 87. You should hear the fuel pump run. Depressing the Schrader valve (use a rag to cover it a bit) should release gas under pressure.
If you do this do NOT leave the jumper in place. That is for test purposes only and careful of the jumper as it might get a bit hot depending upon a few things.

If you do not hear the pump run with the jumper wire and/or if the gas still runs slowly out of the Schrader valve then the fuel pump is dead/dying.

No idea if you have thrown the old fuel filter out but if it is still around try blowing through the inlet side. If you cannot blow easily through it that means the filter is clogged and can be the reason for a failed fuel pump.

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heres a good site to look at for your problem and any future problems.

Hello and thanks for getting back to me!

As I noted, I have suspected the problem was bad gas all along. At this point, I’m just not YET certain what to do next. ( See my response in next post if you care to…much appreciated all around.)

The gas: This car runs best on higher octane fuel. We never put anything lower than mid-grade in it…89 or 90 octane I think.

However, as I mentioned about the gas scare, that purchase MIGHT have resulted in my getting bad gas, I put in a few gallons of the local pumps lowest grade. Ethanol etc. But only about a quarter tank as I feared both buying that cheap gas but also feared having No Gas at all. My tank had at least mid grade gas, with ethanol, prior to that purchase, but tank was already pretty low before that purchase.

In any event, at this point, I think that I might have reason to think that there was enough trash in the gas to clog the line to the gas rail and injectors. But so far I have not narrowed it down.

Great, thanks for your quick, helpful reply!

After reading your reply, I went back out to try to check fuel pump issue:

Here’s where I am now:

I did not rig a jump connection to activate the fuel pump while holding the shraeder valve open. However I did turn my ignition switch on to verify that I could hear the fuel pump priming gas forward.

Upon then immediately depressing the Shraeder needle valve, gas again welled up out the valve but it did not seem to be under much pressure. In fact, after again turning on the ignition switch to activate the fuel pump primer action, I found that the Schraeder valve would produce no outflow at all, apparently. That makes me think a blockage somewhere.

But, also, per your suggestion I did find and blow through my recently discarded older fuel filter. Air flow through the old filter was fine. I do recall being somewhat puzzled the other day when I removed the old fuel filter, and gas flowed freely from it.

So I don’t now know what’s the deal here…I can clearly hear the fuel pump engage and hum…Is it possible that it’s making the right noise but is actually not fully pumping as it should…I’ll keep "a searching for the right next step…

Sounds to me like I might need a new fuel pump, though if I can hear it activate, it makes me think that the pump is either not pumping up to desired pressure.

Alternately, maybe I have a blockage somewhere in the pump or maybe it has a screen in it somewhere that is blocking or reducing flow.

Should I just assume from here that I should next just replace the fuel pump as a next step…

Thanks much!

that would be my next step. but if you want to try something first. take off the fuel filter and put a rubber hose on the side from the fuel pump .make sure its a tight fit. I would use a clamp. put the other end of the hose in a gas container. turn the key and see if gas is being pumped into the gas container. if not or a trickle the pump needs to be replaced.

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Or, put a fuel pressure tester on it?

Some parts stores have free rentals on tools like this.

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Good idea.

Thank you!


And thank you.

Don’t have one, can’t get to town at the moment to buy, rent or borrow one.

Well, dropping tank is no fun. I’d want to know before
5.4 is 3 valve? Not like a 4 valve navigator motor.
Sure motor is good? Lifters. Cams?

@Busta focus on finding out the fuel pressure before tearing your motor apart…

I had a customer with the same problem, it was handles with three questions is it getting gas? is it geting spark? it each happening at the right time? The when I checked out the gas I used a small tank from a Lawn Mower and got it to run right away! Apparently who ever went to the gas station pumped the wrong gas put diesel gas in instead of regular gas, the regular gas floats on top of diesel gas and the pump was able to pump the regular gas but because of the heavy diesel gas it stopped. Most likely the regular gas was used up and that was the end of story!
The customer ended up pumping all the diesel gas out and replacing the gas with regular gas and the vehicle ran great.