2003Ford Expedition engine cutting off while driving for no apparent reason????any suggetions?

 

I just had mine (03 exped) in the shop a few weeks ago for the exact same thing. It would do it a few times then not for months. Then would start again. Driving down the highway it cut out (no sputtering, no noise at all, you could just feel it quit) about a dozen times in the space of about 3 miles. Mechanic insisted it was tied to a bad wire in the remote start system. My husband (a motor head) said no way. But they disconnected the remote start, but a few days later, it started doing it again, so obviously that was NOT the problem. Did you have any luck with yours?

One thing I found on line referenced a faulty coil wire causing that type of problem. But the thing that seemed to make the most sense was a post about it being an ignition relay switch. It said "This is a problem with a lot of vehicles that is overlooked for this reason: when a mechanic hooks up the computer the codes will generally tell you the problem the vehicle is having IF the vehicle kicked a code to the computer. When it runs thru the diagnostic check the system comes back fine and there are no problems. Sometimes the problem can't be found by the computer and the reason is that when the car or truck runs its system check, everything checks out fine! How can this be when the vehicle just stops running and then starts after you pull to the side of the road for a minute? The answer is simple. The ignition relay acts like a breaker in a house. When you have a relay that is weak you will get this problem. But the computer will test it as good because it IS still good. It's just WEAK, making it trip. The reason it will start again is because the relay will automatically reset itself after the relay cools. To explain the type of reaction your car would experience would be as follows: the car or truck will just plain die! No warning! IT WILL NOT spit and sputter. A module for the distributor will act the same way but the difference is that the car will not continue to start after a period of time."

I showed that article to the mechanic but of course (probably because I'm female) he didn't check it. Still insisted it was the remote starter.

 

What engine do you have in the vehicle? If I'm not mistaken, you may have what is referred to as "coil on plug" system. Do you know if you can confirm this?
The more info you can provide, may, help in further hopefully being able to offer useful suggestions.

 

I have a 2003 eddie buarer 5.4.it happened twice yesterday and im getting super frustaded with this expo!!!!iIt doesnt spit out any codes!!1the ignition relay switch make sense.

 

There are a few ways to confirm what you suspect.
The first probably would require a fairly new scan tool.
The second I believe is a little more work , but less expensive and that would be to tie (hook up) a test lite or voltmeter to the output of the relay you suspect and place your choice in the vehicle where you can see it working and if it changes while the problem occurs while driving you will see it right away.
Another option would be to get a second opinion from a different mechanic/technician.
These probably are not the answers you wanted , but it's the best I can come up with at this time. Hopefully someone who has experienced this problem will be of more assistance.

 

It is a 2003 Expedition, Eddie Bauer, 4.5. Same as the other person who has the same problem. Yes it is a coil on plug

 

checked the manual and it shows 9 relays on the diagram, but on the listing of fuses and relays it calls out 14 relays. But the numbers for 5 of them are not shown on the diagram. So now what? BTW, none of them are listed as 'ignition relay.' What else could it be called?

 

Im not sure what finnally fixed the problem for the post starter that said it was the ignition relay.was it the ig.relay after all? thanks for any help im broke down and could use some suggestions thanks for any help..

 

Some Fords have had problems with the PCM power relay. It is located in the Central Junction Box under the left hand side of the dash panel. There are three relays closest to the fuse section. The center one is the PCM power relay. If you have the owners manual , it may make it easier to find your way around the Central Junction Box.

 

Why not hot-wire one relay at a time and see what happens? By hot-wiring it I mean replacing it with a manual switch that you can flip on BEFORE you start the car, and flip off AFTER you turned the ignition off. These relays should be energized as long as the ignition key is in Run or Start, so you can simulate that by hand ... The senior members here should confirm whether this is safe for the electrical system on this car though, as some modules may receive power thorough other relays, and the last thing you want is to have one electronic device back-feeding power though the signal pins into another.

To play it safe, I would solder wires and connectors to a relay, connect a switch in parallel with the relay's contacts, then attach this contraption to the relay socket. Once the relay is energized (you can feel it clicking), flip the switch on so that the relay's possible malfunction can't cut the circuit (now doubled by the closed switch connected in parallel). Drive happily, and don't forget to flip the switch back OFF before you turn off the engine.

Let us know how it goes, and good luck!