Possible bad plugs

[Tom Schindler]

My Sport Trac is running fine. I have close to 90,000 miles on the plugs, but I just don't feel like changing them anytime soon.



The problem is our Mounty. We have a 2006 Mounty with the 4.6 V8. In 2012, I changed the OE plugs (not one single problem pulling the old ones out) and I replaced them with the one piece Champions. Personally, I don't like anything other than a Motorcraft plug in a Ford, but the one piece design was very enticing. Here I am 2 years and 33,000 miles later with a miss. I am not sure if it is the Champion plugs or maybe a bad coil or plug boots.



Anyways, I recall reading somewhere on here that Ford made an upgraded Motorcraft plug that doesn't have the issues of the multi-piece plugs. Is that correct? I don't know if it is the plugs for sure, I am still trying to diagnose the issue, but I am just doing my homework before I make any moves.



I do have this sneaky suspicion the plugs are bad.





Tom

 

[swshawaii]

Fully threaded plugs appear to be a completely different design for the newer 3V heads.

 

[swshawaii]

 

[scott degroot]

I would suspect one of the coils or a coil boot long before I would suspect one of the plugs.

 

[Steve Krusich]

My random misfires disappeared immediately after I removed the one piece Champions are installed OEM Motorcraft! Go figure!

 

[Tom Schindler]

I replaced the plugs. The engine runs very smooth now. No misfires.



Another issue, the fan clutch is stuck on. It does it when cold or hot. Clutch bad?



One last thing, the tranny is starting to shift weird. I don't know if this was caused by the misfiring plugs and now it is noticed with the misfire gone.





Any ideas?





Tom

 

[Vic Sorlie]

Tom, your transmission issue has nothing to do with spark plugs. First thing is to check the trans fluid level. Next questions would be how many total miles on the tranny and how long since last fluid service.

 

[Tom Schindler]

Vic,



I am an AMSOIL dealer (my father is, but I do all the online ordering). The new tranmissions have an adaptive learning system that will adapt the tranny to how shift according to how you drive it.



With that being said, it might have been a problem that reared its ugly head at the same time the junk Champion plugs went south. Don't know.



Either way, it is at the dealer getting looked at. Even got a free rental car. Of course, the wife is driving it, but is ready to give it back. She HATES that CR-V already.



LOL





Tom