Finally figured out what was wrong .There is a junction boxes next to the gas tank that had gone bad.Complete fixed the problem.

 

Also 2003 Expeditions have a problem with a wire that is resting on an airconditioning pipe just to the right of the battery rubbing and causing a short.

 

To all, I have had the issue on my 03 expedition 4x4 a few years ago, cuts off while driving runs ruff,ruff idle. Coil packs seem to go out in twos so don't just replace one it wont help. Coil packs run about 45-$49 a piece. I replaced 3. Years ago and im still running fine. Code reader reader usually I.e. bank1 bank 2, ie., coil packs in firing order 1 and 2. I deal with some of the best mechanics and this has been the fix for me with the similar symptoms you all seem to be having. Lived it,fixed, still running strong!

 

 

Was your problem the actual fuel pump or the Fuel pump control module. I have the same year expedition EB and my fuel pump works but is not getting power. So we are thinking it might be the fuel pump control module under the spare tire or the fuse box relay R303 which is not replacable. My mechanic had cleaned some wires he said had corrosion and it ran for 2 days. he is on vacation and the car will not start only turn over. Any thoughts please help.

 

Could you please answer a question for me?
How do you know the fuel pump works and are questioning the Fuel Pump Driver Module. The pump gets it's power through that driver module. Thanks

 

OK, I have had cut outs at just about every speed and condition. Always restarts in 30 seconds or so. Dealer reflashed the ECU and it made no difference other than problem went away for 4 days! ???? Looked at all wires around the ECU and zip tied them away from air-con lines just in case.

It does act like something is tripping and resetting. I'm hoping it is not the (Very Badly designed) junction box with the non-replaceable relay. I'm wondering if the fuel pump relay control module and/or its connections is causing the problem. Why would a module like that even be exposed to the elements is beyond me.

At the moment, I'm waiting for another ECU from eBay to swap and see.

A little background of weird ECU things on this Expy is: For the last 5 years, it has had a warm start issue. Starts fine dead cold and within 5 minutes of turn off, but 20 minutes and your in for a 10 second cranking. No codes and the dealer was just as helpful with that one. Also, about the same time I notice there was no neutral or park rev limiter on the engine. I know it's not supposed to rev past 4k rpm in that state. Right now it'll rev past 6k into valve float territory.

I'm asking posters that fixed the issue to post their final outcome. I will the same.

140k miles. Fuel filter replaced Engine runs great when running. No fueel flow issues - full throttle thru the gears without a hint of dropping out.