I need a little help with diognosing an engine stall while driving on our 2003 Expedition. While driving on the Interstate about a month ago the engine stopped running but picked back up after about 5 seconds and we completed our trip with no further problems till about two weeks later when it died completely and we had to coast to a parking lot where it would not restart. Next day we go back and it cranked back and ran just like normal. Took it to auto parts store to see if any codes were set but none were shown. Drove it about two more weeks and it has done the same thing again. It stopped running on the way to work and had to have it towed to a shop where it has done the same thing again. It started the next day and mechanic can not find what caused it to die. No codes, fuel pressure is fine and runs like a top. It is a sporadic problem that leaves no clues as to why this is happening! Please help if anyone knows what the problem might be. Thanks!!

 

I had the same symptom on a van I own and it turned out to be a bad crankshaft position sensor. Ironically, the crank sensor is one of the few things that doesn't trigger a trouble code. I'm not saying that your issue, but it's worth looking into.

 

Need pertinent and specific details about what you observe when the failure occurs.

If you want to just take a wild stab at it, replace the PCM Power Relay or swap it with a non-critical (to engine operation) relay. Just don't mix up which relay is which if you go this route.

 

Here's another Possibility. Similar thing happened to me and it was the FP Relay/Fuse box Circuit Board.

https://www.ford-trucks.com/forums/1...xpedition.html

 

When it happened on my 2003, it was the Throttle body. I you're not supposed to try o clean a Ford Throttle body, and but we did and all cleared up for a short time. We ended up finding an OEM Throttle body online and replacing it. Fixed that stalling while driving for good. IAnother problem can be the fuse box on the passenger side, but that simply won't let the truck start. The Throttle body takes less than a half hour to replace and its easy.

Throttle