The Shape
Founding Member
Could be one of the reasons the Ford Motor Company is losing money left and right.
Ford has corrected the spark plug problem. Sounds like any Mustang GT made in Jan 08 or later has the new design.
I believe ANY 2008, regardless of when it was built, has the updated heads. So this would lead me to believe that there are some 2007s with the new heads as well.
Where did you get that information? I believe I read in another thread on this forum (and also on the TSB itself) that the sparkplug issue affects cars built before Nov 30 07:
From the TSB "Affected engine build dates
are as follows: 5.4L 3-V and 6.8L 3-V before 10/9/07, 4.6L 3-V before 11/30/07"
http://www.brokensparkplug.com/TSB_08-7-6_Pg1.pdf
I'm not sure how that's possible...I have an 08' I just bought and on the door sill sticker with the tire pressures it says the build date was 12/07. On the engine there's a date code that is 03-12-07 (I'm assuming that means the engine was built on December third 2007? It doesn't seem to make sense that Ford would have had my engine sitting around for nine months before dropping it in my car. If anyone can confirm or deny the day-month-year format for the engine code it would be greatly appreciated!!). In other words if my car's engine was built on the third of December 07 and the first of the revised head/plugs were going into cars on Nov 30th I wouldn't think ANY 07's have the updated heads.
Any info on dating my engine and/or determining if I have the revised heads would be appreciated though...this thread has me scared!! I know I could pull a plug and check, but I only have 300 miles on the car and don't want to start working on it quite yet...
While I completely understand the change in plug design and the need for it, can someone please explain what changes were made to the head to compensate for the plug issue?
Wish I could find the pic of the new head. Its posted on this site but haven't tried the search function yet. Basically the plug hole is threaded right down to the combustion chamber now just like the old days. They got rid of the non-threaded "tube" part of the head that the plug used to go through. That way there is no way for the plug to corrode and stick to the head. The 08 F150's with the 5.4 also have this new head and plug design. The plug itself is way shorter than the current one and looks like a plug from an old 302/351 V8. Much better IMO!
The TSB say 11/30/07 for a reason. ALL Job 2 engines have the new heads and plugs. The Job 1 engines mostly have the old style but there could be some with the new style. You need to check.
I just rolled 20K on my 2007. I have told the dealer that I will be coming in to get new plugs done.
If you use the new one-piece plugs from Champion (or whoever), would you still coat the plug with anti-seize?
Some people representing Ford don't seem to know WTF is going on. I talked to an "expert" at FRPP during the Woodward Dream Cruise. He told me the only people having this problem are those that do "quick trips" and don't allow the engine to get fully warmed up. I told him about the anti-seize solution and he said he would never put that on as it would "melt off." I told him the melting temp was higher than the engine temp and he said, "It gets pretty hot inside the combustion chamber."
This whole thing is really a pisser, isn't it?
Sorry, but I have to throw the B.S. flag on this one. I started to change my OE plugs at 38K miles, not many of which were "quick trips" and the second one snapped (following the TSB to the letter). Trucked car to dealer where they broke off 5 more.
I would still use the nickel anti seize. I stop applying maybe 1/4" from the end of the "barrel", and use only a thin coat. That's what I did and haven't had a single problem since. BTW, I replaced the POS Motorcraft plugs with the one piece Champions and never looked back.
There is a sticker on the driver side valve cover that will have AA or AB in the number. You are correct AA is for the old style heads with the pos 2 piece sparkplug and AB are the new heads for a one piece sparkplug the way it should of been made from the beginning. Geeezz.
If you look at the sticker on your driver side door jamb and find the date your car was manufactured as long as it is after that date, then you are fine. Before that you might want to go to a parts store and pick up the new plugs.These were produced after 11/30/07.