I was just reading about the 3 valve 4.6 L engines that our Mustangs have and the issues with the plugs breaking off as you try and remove them. I only have a little over 5000 miles on the 07 GT/CS that I just purchased and now am a bit concerned about the plugs.

Have any of you replaced your plugs to avoid this problem of the OEM plugs breaking off or do you think that the stock plugs will last up to 100K miles and just to leave it as long as it is running good?

Additionally, has anyone had plugs break and how tough was it to remove the broken part of the plug?

Any TSB on this as well?

Thanks in advance for any insight on this!

Phil

 

Yes they can be a problem but that is usually when guys try after several years and like 75-100k miles. Several threads here about it.

Carbon builds up inside between the threaded portion and the extended barrel. Which then causes difficulty in backing the entire plug out. The plug can break leaving the barrel in the cylinder.



Yes there is a great TSB and if one follows it closely, the plugs often come out without a hitch.

If it were me, with only 5k on the clock - therefore there isn't enough miles that they're loaded up with carbon, I'd change those 2 piece out and put the re-designed 1 piece in now. Problem eliminated for just a few bucks.

 

This!!!

 

I misspoke a bit there. Although some carbon can build up where I said, the real build up is between the extended barrel and the hole in the cylinder head that is passes through.

Ford redesigned the heads so the plug doesn't need the extended barrel. Like a normal plug. The new heads were released 12.07.

 

I have never had a problem with my 07 GT/CS. but I do change out plugs every year (Saleen Blower). I also place a small amount of Nickle ( or is it copper) anti- seize on the barrel. I use the Autolite HT0 plug.

 

Why chance it when you can get a one piece plug?





https://themustangsource.com/f637/sp...3/#post6643067

 

He says he has blower, so he's probably running a colder heat range and the only one piece I know of with a colder heat range is the Brisk, which are about $17 per plug.

 

Thanks guys!
Really appreciate the info.
What is the best 1 piece plug to replace the 2 piece plugs with on a pretty much stock engine?
Thanks again,
Phil

 

Do you have brown coil boots or black coil boots? you may not even have the problem plugs.

 

I think they are black, however I will have to recheck.

When I am able to check later this morning, I will advise.

The black boots indicate the 2 piece plugs, correct?

Thanks much!

 

Yes black boots are the two piece plugs, I think they changed the design mid 07.

 

Just checked.

Yes, they are in fact the black coils with the black boots

So, I guess I will try and figure out what will work best as a replacement single piece plug.

Thanks again,

Phil

 

IIRC they changed the heads for '08 so the plugs were also changed. I run Brisk silver plugs, they are a tad pricey.

 

The new heads were released 12.07.
In time for Bullitt. Mine was built 1.9.08. Has brown boots.

 

I'm at 100,000 km (62k miles)
This should be interesting ....
Car is an 05, so we'll see how this shakes up.

 

Mine was built 1/28/08 glad I made the cut! LOL

 

Ordered spark plugs from AM and Motorcraft anti-seize from Amazon. Probably find out that my plugs are fine since I have only a little over 5000 miles on the Mustang, however I always try to fix any issues before they happen!
Thanks everyone for the info!
Phil

 

follow the tsb closely and you should be fine. Let them plugs soak a long time.... over night at least.

 

I agree. I'll bet a dozen doughnuts they back right out.

 

[QUOTE=Phil_R;6785363]
Have any of you replaced your plugs to avoid this problem of the OEM plugs breaking off or do you think that the stock plugs will last up to 100K miles and just to leave it as long as it is running good?

Additionally, has anyone had plugs break and how tough was it to remove the broken part of the plug?

Any TSB on this as well?
/QUOTE]




You already have the best plug in your vehicle in my opinion. I've never had good longevity with Champion Plugs. I have my own worries with the one-piece plug. Say if the barrel sticks bad enough to allow the plug to break, where will it let go? Maybe between the thread and the hex nut? I don't know but don't want to find out. I've change two-piece plugs at least 4 times at work in Expeditions and never broke a plug using the TSB and pre-breaking loose the plugs and then letting them sit overnight with the Ford cleaner spec'd in the TSB. Some of these trucks had in excess of 60000k on them. Yes, when I removed some the barrel did come loose but they never separated.


Here's the TSB... http://www.phila.gov/fleet/Warranty%...-06%20FORD.pdf