Hey everybody, I have a spark plug question. I've been keeping my eye of all the forums about spark plugs, and all the drama that comes with it. It seems that all the problems are the ppl that have a 5.4L. Are there any problems with the plugs in the 4.6L. I'm running a 2004 STX with the 4.6L, and its getting about time to change them out. I try to do as much work as I can to keep down on repair costs, but I'm needing advice.

1) With all the problems that are floating around this forum, is it better to take my truck to the dealer and have them do it, or can a shady-tree mechanic do it without any problems?

2) If I decide to take it in to the dealer, are there any headaches I need to know about a head of time?

3) Are there any special tools needed to change them out, or would a unversial plug wrench take them out?

4) Whats the best plug to replace the factory plug, and whats the gap?

I'd appreciate your feed-back. Thanks again.

 

the 4.6L 2v doesnt have the problems that the 5.4L 3v does. Get a spark plug socket and some extensions, preferably with a wobbly end on one. A little dab of anti seize will help on the new plugs, gap them at .054, and for plugs, get some Motorcract coppers in AWSF-32C..if those arent readily available, Autolite 764 is OEM heat range.

 

Do not use antiseize on the spark plugs. It multiplys the torque. Put the plugs in with a small dab of oil on the threads thats all you need. Make sure to torque them to spec. I don't remember what it is right off the top of my head.

 

Then what makes the 5.4L worse than the 4.6L?

 

crank them to 1/4 past hand tight.............


the plug design and the fact that the head design is completely different between the two engines.

 

Read this post here, post 4 has a picture of the newly designed plugs. Here is a video of the removal procedure (Episode 26, 3 valve engine spark plug removal). This should help explain the issues with the plugs. Only the 3 valve engines have the new head/plug design. 4.6l 3 valve engines are used in the Mustang GT, Ford Explorer and Mercury Mountaineer.

 

How hard was it to actually get the plugs out? Did you break any in the process. I checked out the two post, Post 4 was helpful, and I couldnt get the video to play. With this experience, is it easier jus to have it taken it, or or do it yourself? I can understand by doing it yourself, you have faith in your own work, but how much work is ahead of me?

 

the plug removal process is NOT the same among the 4.6L 2V and the 5.4L 3V. remove the coil, insert socket and remove, reverse the process.

 

that being said, I can knock out 7 plugs in my car in about 15 minutes.

 

I didn't realize these trucks were such a job to change plugs in.