hey guys i could really use some help with my 2002 f-150 4x4 5.4eng. changed the oil the other day then i sprayed some engine cleaner and washed off the engine. i think i got something wet that shouldn't of gotten wet. the truck runs rough and has a low idle about 500/600 rpm, (it was running normal at about 900rpm.) now the service engine soon light is on and flashes 40 then goes solid. any help or thoughts would be great. thanks chad...

 

Is your truck still running rough,it should have dried out with some easy driving.

 

hey darrell thanks for the reply, and no truck runs pretty weak. i tried to dry it out with easy driving at about the 10 mile range. still weak off the start and at idle, i got a new coil just need to find the bad one and replace it, i hope that is it! if not off to the dealer i go. thanks for the reply and if you have any experince that would help you can post or pm me, later chad...

 

Sounds like water may have gotten under the distributor cap, of course there is not one on a 2002, but that was a common problem with older vehicles I still drive!

 

when you washed your motor you more and likely got water in down the cylinder where the coil goes in. you will have a hard time drying it out by driving it. All you have to do is find out what plug is missing your check engine should beon. When you find out what hole ismissing take the coil out and blow in there with compressed air untill all the water is gone. just put the coil back in.You may need a new plug.

 

thanks greuelc, i checked for misfires by unpluging each coil one at a time while engine was running. when it ddnt seem to change i pulled that coil and yes there was water and contensation on the coil leg and in the housing/spring, i tried to dry it out good but might not of got all the water out or i may have two coils flooded i will check it tuesday (day off) and post reply on how it went.... thanks again for your help chad...

 

well thanks guys and hayapower for all the help. i think the f-150 is fixed seems to be running pretty good. and i did change my spark plug that was in the flooded clinder(it looked bad). reset the service engine light and drove it for about 5 miles heavy footed, and no light and good power, so i hope it is fixed, thanks and mahalo all....

 

My 5.4 did the same thing when I washed it. Two cyllenders missed. I took out the plugs and cleaned out the plug holes. Spraying with WD-40 helps. It replaces moisture. Solution: Never wash engine again!!

 

Just bought an 06 5.4 and and wish i would have read this post first but all turned out ok, sprayed engine wash and hosed it off at the car wash. came out nice. The owners manual actually says towash the engine. They say to cover the battery and air box. all the same, not something i want to do to often, it would be embarassing having to have a tow truck give you a lift home from the car wash.