I cleaned out the engine compartment with Engine Brite and hosed it down today. After getting it pretty good and cleaned I let it dry for a bit and then started it up. I imediately noticed that the engine was running pretty rough, especially at idle and about 45mph. The check engine light came on and I hooked up the OBD II scanner and it says the #2 cylinder is misfiring. Everything is pretty dry under the hood so I wouldn't think that water would still be interfering with anything. I was thinking that the spark plug is shot, but before I go ahead and replace the plugs. Does anyone have any ideas of what it might be, so I don't have to go through the process of replacing the plugs?

 

Have you tried letting it dry for a little while longer? And is the miss still noticeable? Any time water gets into some electrical connections, there is the possibility of screwing things up...but 99% of the time those problems resolve themselves when the water dries up. I'd try a blow-dryer if you don't have an air compressor to get it really dry. Even once the miss goes away, the light will stay on until it's either reset or until you make 2 or 3 trip cycles...which is basically x amount of time under 30, x amount of time accelerating, x amount of time between 30 and 50, x amount of time doing this and that...so depending on your driving habits, it could take a day, or it could take a week for it to turn off on its own.

 

Its been drying for about 4 hours with the hood open and under the sun. It's pretty dry, and checked all the wiring around the plugs and injectors. They are connected and dry. I was gonna wait till tomarrow morning to try it again. Could water have shorted out the COP?

 

Yes you could have fried it.

Disconnect the battery for 15-30 min,drive it and see if it helps,if not you will prob get that code again.

 

It's possible, but you have to remember, those connections are pretty sealed off. Some water gets in, but it takes a while to dry. Have you tried a blowdryer yet? Either way, it should be good by morning.

 

just tried the blow dyer for 20 mins or so. Still no good. I'll just have to wait till morning. I agree that the coil pack is sealed but if it still misfires tomarrow, it'll probally be the coil pack, right? If so, any advice on replacing that?

 

Wow, I just had the EXACT same thing happen to me, I ended up changing the spark plug and it fixed everything. I drove with it for about 4 days hoping it would dry up but no.

 

strange. did you have trouble getting the spark plug out. I've read on here that sometimes the carbon buildup can make it really tough to get out or could even break the plug, causing a whole new mess of problems. Anything like happen?

 

This is a VERY common problem associated with wetting the engine. All you have to do is remove the #2 coil and dry it out. Remove the spark plug and dry it out. Put it all back together and everything will probably be ok.

If you still get the missfire, you may have ruined the coil. But drying it out almost always fixes it.

 

thanks. I'll try all of that tomarrow.

 

I just tried running the truck after letting it sit overnight. The engine isn't nearly as rough as it was, but I can still feel it vibrate more than it should. Especially when I go in reverse. I'm gonna go ahead and change out the spark plugs and the coil plug for the #2 cylinder (don't have the money to do all of them).

 

You don't have to change the spark plug. It is fine. You probably don't even have to change the coil, just dry it out good. They get water in the boot. I don't know how, but they do. just dry it out GOOD and put it back on. It will probably be fine.

 

Water penetrates the cop boot. Dry out the boot,THEN use diaelectric grease IN ALL your cop's boots to prevent any reoccurrance.

 

Ya if it's not running as rough as it was prob still wet,cop is prob fine

 

And quit washin' yer engine.