I have a '97 Expedition EB with just under 90K on it. The truck is not driven very frequently as we have more economic cars as commuter, but we do use it for towing our camper and other "work horse" related things.

During a recent snow storm, my wife used the truck to haul the kids around and had put it into both AWD and 4WD-High. SHe mentioned that while she was driving it the Check engine light came on. I took the truck out to see what she was referring to, and here are the symptoms.

I drove the truck to a supermarket about 2 miles away.
When I started the truck it was idling very rought (lots of cabin vibration) and the check engine light was on solid
After driving about half way (1 mile) the check engine light began to flash.
Went into the market for about 15 minutes and when I came out to drive home the check engine light did not come on and never came on the whole drive home.

Today I decided to drive the truck into the office (about 5 miles from home)
Again when I started the truck the check engine light was on solid and the vehicle is idling very rough
About 2 miles into the trip the check engine light went to its flashing mode again.
After about another mile it when solid again, and then the last mile and a ahlf or so it started flashing again.

The engine is definitely idling and running rough. I am getting a lot of vibration through the steering column and in the cabing especially when I get it up to higher speeds (or at least it feels more pronounced).

Any thoughts or recommendations are appreciated.

Eric

 

Well, I took it into my mechanic and the #4 coil was shot. Had it replaced and the truck is runninglike a dream.

Eric

 

Glad it was a reasonable repair......