I have a 98 F150 with a 4.6L. When we receive 1" or more of rain, my CEL posts within a day of the rain. This has happened about 4 times in the past year. Each time, the code indicates a misfire on #7 or #8. I resolve the problem by removing the spark plug boot, observing the water in my spark plug tunnel, and blowing out the water with compressed air.

My question is: Is the water coming from a bad hood seal, a water leak on the engine (which I doubt, since it coincides with a rain event), or a bad spark plug boot (is the boot suppose to keep water out of the tunnel)?

Thank you in advance for the assistance.

 

It is usually the hood to cowl seal that lets water drip into the engine bay.

 

I ordered a new hood seal from a Ford dealer in Texas. However, once it arrived, it was obvious the design was different than the original seal. The length is correct, but the cross-section of the seal is significantly different than the original. I sent a photo to the dealer, which compared the two seal designs, and asked if they could help me. They won't reply.

Does anyone have experience with replacing a hood seal on a 1998 F-150? My old clips don't seem to attach well to the new seal...do I need special clips with the new seal design?

I attached a photo of the two seal designs below:

 

Like a lot of parts you buy, certain things are not included. Mine was slightly different...as yours is, but I also ordered new push in clips. New clips and you will be good to go. Good Luck!

Don't waste your time with that dealer. Call another one and ask them...a sharp parts guy will have the answer on the spot. I have four Ford dealers I will call if I need something, and it amazes me how inept and rude some can be over other dealerships.