Ford 2003 Expedition apparent insufficient fuel flow

Maintenance/Repairs
1

Any leads on diagnosing this issue will be much appreciated!

A year or more ago, I got this car running again after I bypassed the fuel pump relay and also did a DIY injector cleaning by repeated pouring Berryman’s B-12 Chemtool straight into throttle body throat, in small amounts, then cranking with starter spray. Car first only sputtered. Got better with repeated injector treatments outlined above and soon ran fine.

Recently, it stopped behaving!

I can hear the fuel pump prime and I THINK I’m getting fuel into the fuel rail…though not certain. At least once, by depressing schraeder valve needle, I got fuel there. But I am not absolutely sure fuel rail is fueling 100% nor have I checked pressure. (No gauge, getting one tomorrow.)

Engine fires right up with Starter fluid, and it will sputter along a brief while if I have “pre-treated” with Berrymans. However, the accelerator apparently sends no gas flow. Or maybe something else in the fuel/air flow is awry.

I will replace fuel filter too, but given the fact that the engine had been running fine but then one day out of the blue just suddenly stopped mid-crank, apparently because no fuel flow, doesn’t seem like a fuel filter build up clog, to me. (But what do I know!) Current fuel filter is not that old, either.

Fuel pressure gauge may help further diagnose, after I check rail pressure.

Meanwhile, any advice on this much appreciated!

2

1st thing, make sure it has gas in it… gas gauge could be faulty…

Once you remove the fuel filter, take a white paper towel and put it on something hard like the floor or work bench and tap the inlet side of the filter on the white towel, look for anything that could be stopping the filter up like trash in the tank, even rust, yes I have seen rust in a plastic tank with just 30K miles on it, can you say bad gas… lol

Once you have checked and replaced the fuel filter and performed the fuel pressure test, give us an update on the results…

3

What was the repair you did after bypassing the fuel pump relay. Surely you haven’t been driving that way.

I imagine the check engine light is on. First check for fault codes. Then test fuel pressure.

4

Uhhhhm. Right. Do that and report back. Having fuel at the schrader valve means nothing.

5

Thank you! Very helpful. Definitely plenty of gas, though now that I think of it, the first abrupt halt in engine performance two years ago came just after I put low octane “Regular” in the tank at a station whose gas tanks were drained low. Now after thinking about it, I’m wondering if low quality gas, maybe dirty, might be a factor here. Due to finances, I recently quit relying solely on mid octane or high test gas which I had relied upon after getting the car going last time. Maybe that’s a stretch, but your advice on tapping the gas filter is on point. I have wondered if there might have occurred some blockage in the filter sufficient to suddenly block glow altogether.

Thank you. More later.

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6

Yes, I have been driving the car after bypassing the fuel pump relay. Ford on this model welded the relay onto the back of the fuse/relay box. It’s not plug and play. New central box would be $600. Can’t afford that at present.

Has cranked and run fine this past year after my DIY by-pass fix, until the recent, sudden shut-down I did check the 20amp fuse for the fuel pump and it was fine. In short, I can hear the fuel pump cut on when I turn the car on, but no gas or almost no gas is getting to the injectors. Or, maybe the injectors aren’t activating. I did not know how to address that. Again, car fires fine with Starter spray, but then sputters out.

Per codes, I get nothing under “No Stored Codes” under my year/model Ford Ex.

Under “Pending” I get two: 1) Monitor checks not complete, needs to be driven; 2) P0232-Pump Secondary Circuit High

I don’t know where to go with that.

So, my current action steps are: 1) Buy a fuel pressure gauge and get that reading 2) Replace Fuel Filter.

Thanks for your input on this!

7

OK, thank you! That is timely, key info! I will check back with you on that.

8

This does indeed sound like a problem with the fuel system. The power-train computer is what causes more gasoline to flow into the engine, by increasing the injectors’ pulse length in rsponse to more measured airflow. Seems posssible you still have some sort of injector problem. Knucklehead diy’r opinion, no 03 Exped experience.

9

OK, thank you! 1) At present I’m still trying to determine if any gas is getting into the fuel rail. I have a loaner fuel pressure test kit from AutoZone. But prior to that check I need to replace the fuel filter, just to cover that base. (Even that little job is hard to do in this cold weather. You have to really press down hard on the tabs at the three connection points, as I’m sure you know, and then also use a little elbow grease even still. I managed to remove filter the other day in order to see if any dirt or grit came out of it. It seemed fine so I put it back on. However, now, I’ve decided to put on a brand new one. Hard to remove the old one with frozen fingers! Try again tomorrow with aid of same little trick I used Sunday to depress the release tabs and pull the old filter free.

  1. Your comment about the power train computer maybe interfering with the flow to or activation of the injectors…sounds like a good lead on a diagnosis step once I get the new fuel filter in place and then check fuel rail pressure.

Question: Do you know how that might show up on my code reader?

Thanks again!

10

Don’t worry about the fuel filter.

You’re testing for pressure not flow.

Tester

11

Sorry if I missed this…but could this be a fuel pump going bad? With 22 years on the clock, it’s certainly a possibility.

12

Yes, in limbo right now awaiting the fuel pressure test results…

13

Insufficient fuel flow/pressure might show up in the real-time fuel trim data. The powertrain knows how much fuel is injected (for a properly working injector) for a given injector pulse width (time). The powertrain computer calculates the injector pulse width based upon several inputs, the main one being the measured airflow into the engine. If the injector is injecting less fuel than it should, that will confuse the powertrain computer. This problem seems unlikely to be caused by the fuel filter b/c it is happening at idle rpm. Fuel filter problems tend to show up more in high fuel flow driving situations, going uphill fast, etc. But a faulty fuel filter might cause this, and since you want to install a new one anyway, seems as good of time as any. I’ve never had to deal with those tricky fuel filter connections myself. But I can certainly understand they’d be even more tricky in super cold weather. One caution, be sure to follow all the common gasoline safety precautions.

Disclaimer: I’m just a knucklehead diy’r opinion, no 03 Exped experience.

14

OK, my sincere thanks to all of you for your interest and comments on my 2003 Ford Ex. I also apologize for my delayed responses and updates. Three kids in and out of school and temps in the teens stopped my shade tree DIY cold.

Any further interest and input will be PROFOUNDLY appreciated.

Current status then some (possibly) relevant context:

  1. New fuel filter in place.

  2. Fuel rail pressure reads Zero. Nada. None with car key switched on.

Still nothing after cranking with starter fluid. (Here the car cranked right up and ran for quite a bit longer than I’d expected with just a fairly hefty one shot of starter fluid PRIOR to key ignition. And activating my foot pedal to throttle up seemed to work at first, but soon car died. Won’t crank or run without starter fluid).

I don’t know if it matters at all, but some history here: The combination of injector cleaner and starter fluid definitely served well one year back when I jerry-rigged a fuel pump relay bypass to get the car running again after it had sat for two years. It then ran hardly at all, then roughly, then well after repeated treatments with Sea Foam and/or Berrymans injector cleaner and starter fluid. Ran well all year on my admittedly jack-leg one wire by pass at the fuse box.

When it quit this time, at least two weeks ago, it quit suddenly when I cranked it–fired strongly as it always does, then 1/2 second later engine fabruptly stopped dead. And I do think I heard it MAYBE make a clicking noise at the fuse box when it went out. I first thought maybe my by-pass wiring disconnected. I double checked that plus checked relay fuses at the box, OK.

However, I have not checked all possible relevant fuses in the box. Is it possible something else went out for another relay or connector switch that might interfere with power to the pump or interfere with gas transfer after the pump turns on.

Maybe I did not have my by-pass re-route properly grounded and thus eventually tripped or blew out something in the power line to or at the pump. Or blew out the pump itself. Maybe the pump just flat out died.

One more relevant context note here: The whirring, running noise I still hear coming up from my back right quarter panel area when I turn key on–I had assumed that that was the fuel pump pre-start function. Runs two/three seconds. Stops. I usually repeat the key on pre-start process in effort to ensure SOME gas flow.

So I don’t know what is coming on back there if it’s not the fuel pump.

As a test, I even disconnected my fuel pump relay wire at the box and then switched key on. Whirring run noise still coming on short while, then dying. So at this point, I’m basically lost in the cosmos.

I have not yet followed up on the no pressure reading with the multi-meter that is included in my loaner pressure gauge kit. That’s tomorrow.

Honestly I don’t know where to start with the multi-meter, not even what setting to use on it. I’m attached a photo of the multi-meter face–any advice on what setting to use or what circuits to test, in what order–MUCH appreciated. (Here’s where my tenderfoot greenhorn ignorance really shouts out loud!)

There is a good '03 Ford Ex YT video that includes what to test where, and when. I’ll find that again as well.

Sorry for the novella here. But with advice I’m getting here plus YT stuff, I’m taking baby diagnostic steps.

Thanks again to you all!

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15

You need to make sure you are getting voltage to the fuel pump, if you are and the ground circuit is good, then you will have to pull the fuel pump and make sure the fuel pump sock is not clogged, but it sounds like you have a bad fuel pump…

Do not buy an Airtex fuel pump, pr a AZ brand one, they are junk… Just for ha-ha’s, check the right front kick panel (IIRC) at the top for a big red button, push the big red button firmly and see if it will start…

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16

Great. Thanks.

I’ve already checked the fuel cut off switch, the red button.

But, question: To check the voltage to the fuel pump and/or the ground circuit…I’m not sure of my current status on the gr. circuit.

As noted before, to by pass the fpump relay, I previously just ran one wire from the car battery down to the correct slot on the unplugged plug-in connector that sends power to the fuel pump.

I should have bought the right gear to splice in a proper connection at the fuse box.

Should there be a separate ground circuit wire? (Please excuse my rank ignorance on this. Maybe I should just start the multi-meter testing as if I’d never bypassed the relay?

Also, which setting on the multi-meter?

Thanks again!

17

I had to do the same thing on one of my vehicles in order for it to run.

In my case, the driver for the fuel pump in the computer failed. So, I drove the vehicle with jumper wire installed until I could find a replacement computer.

Tester

18

Use the 20 V setting to test for power. Use either the yellow dot or the 200 ohm setting to test for continuity. The yellow setting should give you a beep if there is electricity flowing.

19

Thank you!

20

Ford designed the fuel system w/a pump relay for a reason. Probably b/c w/no fuel-pump relay, other parts of the circuitry may be passing more current than their design allow. The fuel pump consumes a lot of current. I’m just a knucklehead diy’er, no claim to be 100% correct, but it is possible some damage to other parts of your circuity has occurred by bypassing the relay. If so, that would show up as lower than expected voltage measured directly at the fuel pump.

Note: When you alter the car’s wiring/circuitry, you run the risk of a car fire. Suggest to discontinue this practice.

Also note is is also possible the reason you Exped won’t start is b/c the engine is flooded w/gasoline.

Diy’er opinion only.

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