When I get a car wash on my '98 Expedition 5.4L V8 the engine sputters for the rest of the day. Sometimes the check engine light even comes on. I figured something electric is getting wet. I'm guessing the undercarriage wash is the main source of the problem. I had the spark plugs changed out and the wires as well. I went right to the car wash following this and it sputters and hesitates on acceleration again. Anyone else experience this annoying problem? I would appreciate any help. Thanks.

--Mountain Cat

 

Probably a COP getting wet.

Try a spray bottle while in your driveway, hitting each COP, one at a time, to see if you can find out which one is hydrophobic.

Steve

 

I'm trying to recall if there is a gasket that runs across the cowl that snugs up to the underside of the rear edge of the hood. If so, I would ensure that it is in good condition and not allowing pressurized water to sneak in and douse a COP or two. Cop's don't take too well to repeated $oaking event$.

 

I had the same problem on my '99 Expy with 5.4L engine. turned out to be #4 COP. What a bytche that was to change out..........

Wilkinda