I am looking at buying a 2005f-150 KR 4x4 with 45,000 miles. The guy I am buying it from took it to a detail shop and they washed the motor. Now it has a check engine light and it is missing. I told him it was probaly the COP. He said the mechanic checked them and they were ok. I need some help on this. I will try and get the code the truck is giving. Thanks for the help.

 

Look for moisture in the spark plug wells. Even a very small amount will cause a COP to misfire badly. After a while it seems put microscopic holes in the side of the rubber boot and the COP fires to ground through to the side of the head in the plug well. A trouble code should tell you exactly which one (or more) is misfiring. If you can't get a code reader you could pull each COP and look for what looks like small spider webs in a circular pattern on the side of the rubber boot that runs down to the plug (this is carbon tracking by the way). That is where the misfire is. In addition, if you have any moisture at all when you pull them out dry it all out thoroughly. The COP's are supposed to seal to the side of the plug well, but high pressure washers can force some water down into the plug well. It happens quite a bit when cleaning engines with a pressure washer, especially when they are a few years old..

 

Thanks for the tips. I havn't talked to him today to get a update. How long will it take for the water to dry if he dosen't take the COP out? Thanks

 

I just talked to the guy and he said between him and the ford dealer they figured out the truck isn't keeping time. Whatever is suppose to keep the motor in the right time went out. I am sorry I don't know what the specific part is. Thanks for any help.

 

Sounds like a diferent problem. Possibly a sensor that failed after getting wet. Shouldn't happen but the problem could be unrelated to the engine washing.

The water will take a long time to evaporate on its own. It tends to get trapped in there. The fastest way is to take the misfiring COP off and wipe it dry. Then let it sit a few hours to fully evaporate. This has cured the problem on a few other COP Fords.
Good luck, and I would be curious to see what the problem turned out to be.