truck has been running really rough for the past couple months and im finally getting time to work on it...im throwin codes: po171,172,174 which is a lean and rich on both bank one right? also misfires on cyclinders 2,3,5, and 6...What gasket do I need to replace to keep oil off the spark plugs? Think I may have a clogged/broken cat because theres a rattling noise inside my driver side rear one so I think im just going to delete the rear ones..Any help greatly appreciated..Thanks

 

In all likelyhood, your MAF sensor is giving P0171/2/4 codes. Misfiring could be the cause of it too, especially if that code is given for those cylinders. Start with a new coil pack, plugs and wires and see if that doesn't solve all the problems. While your at it, clean the MAF sensor. The oil on the plugs is a weird problem, no spark coulda causes the cylinder walls to be washed down with gas maybe. Might also be the head gaskets are going, which is common on these engines.

 

Could be the MAF sensor... but I'd try the plugs first... it's a quick 1/2 hour job and I insist on Motorcraft ONLY.

Also, BLUE20004x4 your post is slightly incorrect. The headgaskets on these engines are fine. It is the intake manifold gaskets that are problematic on the 97-early 98 trucks. Which the OP has a 2000 so it would not apply to him. Besides, it wouldn't be oil, the intake manifold gaskets leaked coolant into the cylinders causing the dreaded hydrolock issues.

If you have oil around the threads of the plugs, I'd consider looking at the valve cover gaskets.

 

Yes, that's what I meant to say, do the plugs first etc. That was the other gasket I was thinking of, intake. However, I've always heard the head gaskets were crapola too. Mind you this was early 90's I'd say when the Supercoupe 3.8 was around. I use to build the 3.8/4.2 at Essex Engine Plant around 99-01 and heard of alot of Windstar engines having bad head gaskets too. Who knows, every one I have seen is fine so what can ya do. The other issue with them I'd say is the IMRC, expensive pain in the butt.

Hey OP, put silicone dielectric grease in the spark plug boots as well, a good glob anyways!!

 

didnt get around to messin with it this weeknd like i planned but im going to try during the week...put new plugs, wires, and coilpack in about 6 months ago so the wires n coilpack should be good but i kno the spark plugs are done for but its just going to keep happening... when i changed them out i put in the motorcraft plugs and it was all good for like a week or so and then ran worse than before i changed all of it and pulled the plugs n it looked like the piston smashed three of them cuz the tips were gone of them so i put in some autolites like i had before and these have stayed together good so far their just all carboned up now some being worse than others also the truck idles really crappy but like in higher rpms like 2500+ it seems to run fine..