I just changed the plugs on a 97 F150 I just picked up. It has the 4.6L V8. I found that most of the plug wire boots were very difficult to remove, but the plug boot for the #3 cylinder was IMPOSSIBLE to remove. I used the largest pliers I had to grip it, and pulled with ALL my strength, and naturally the boot tore in half, and I then had to fish out the remainder with needle nose pliers. There is 81K on the truck, and the plugs looked quite used up, so they were probably original. Has anyone had this experience? Is there some trick I didn't follow? Is there something I should do to prevent this?

 

...and I changed plugs at 45,000. They looked OK; installed Bosch +4s. Now at 97,000 and I think I'm gonna change them again once I get myself mentally prepared for the freakin' hassle. This time gonna also change plu wires.

Although I had no trouble getting plugs off, I think some posters here have mentioned using dialectic grease on the plug boots when reinstalling to prevent your problem.

 

Do you offroad? Water and mud can get in there and cause problems.

I think your answer is to change them more often, that's way over the service interval for those things. I had to change my plugs and wires at 30,000 miles because the truck started running like crap, then again at 60,000. I can do the whole job in about an hour now.

Oh, be SURE to use dielectric grease or you will have the same problem next time.

 

Thanks everyone... I never used that stuff (it is non-conductive, right?). Where exactly do I apply it? To the ceramic part of the plug?

 

Man, you had the same problem I did! I couldn’t get the #3 wire out either. I used a large flathead screwdriver to finally wedge it out and in doing so, I tore the boot. I installed all the new plugs and I used the same wire again. Unfortunately, it didn’t work. The wire was arcing between the tear and the manifold and it caused the cylinder to miss consistently.

So, I went out and bought all new wires. It’s probably for the better anyway. There is a goo that is sold for fixing this very problem. You rub it on the outside of the boots and it’s supposed to prevent them from sticking.

I don’t off road and my engine had 100k on it.