It's a GT, so it has the 4.6 2 valve s.o.h.c. engine factory rated at 260 horsepower. Ford fixed the intake manifold issue for the '02 model year, but I am wondering if the 2003-04 model year with this engine had the spark plug ejection/stripped threads issue? Please comment if you have any knowledge or first hand experience with this.
2004 Mustang GT
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2004 2V 4.6L engines still have the short threads, Pretty sure they didn't get full lenght threads 'til 2008.
OVERKILL
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It's my recollection that the plug launch issue was fixed for the '03 model year? My '02 Expedition was definitely affected by it.
Originally Posted by A_Harman
No, the spark plug thread issue is only on the 3-valve engines.
YMMV, but I can confirm I personally had a spark plug eject from a '96 GT 2V. Owned an '04 GT as well, never an issue with it. One of the best cars I ever owned (reliability).
No, the spark plug thread issue is only on the 3-valve engines.
YMMV, but I can confirm I personally had a spark plug eject from a '96 GT 2V. Owned an '04 GT as well, never an issue with it. One of the best cars I ever owned (reliability).
OVERKILL
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Originally Posted by A_Harman
No, the spark plug thread issue is only on the 3-valve engines.
That's the plugs getting stuck (2-piece) and breaking off issue. The OP is concerned with the plug ejection issue, which was a 2V problem.
No, the spark plug thread issue is only on the 3-valve engines.
That's the plugs getting stuck (2-piece) and breaking off issue. The OP is concerned with the plug ejection issue, which was a 2V problem.
The plug ejection problems were primarily the 5.4 2v. The stuck plug problems were the 5.4 3v.
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Originally Posted by PowerSurge
The plug ejection problems were primarily the 5.4 2v. The stuck plug problems were the 5.4 3v.
The 4.6L, 5.4L and 6.8L all suffered from plug ejection in 2V trim as they all had the 3-thread heads. The truck 5.4L and 6.8L seemed to have more frequent occurrences because they likely experienced longer periods of elevated cylinder pressure.
The plug ejection problems were primarily the 5.4 2v. The stuck plug problems were the 5.4 3v.
The 4.6L, 5.4L and 6.8L all suffered from plug ejection in 2V trim as they all had the 3-thread heads. The truck 5.4L and 6.8L seemed to have more frequent occurrences because they likely experienced longer periods of elevated cylinder pressure.
Originally Posted by OVERKILL
It's my recollection that the plug launch issue was fixed for the '03 model year? My '02 Expedition was definitely affected by it.
Interesting......I have seen it happen on trucks as late as 2005. The TSB covers up too 2008 model years.
It's my recollection that the plug launch issue was fixed for the '03 model year? My '02 Expedition was definitely affected by it.
Interesting......I have seen it happen on trucks as late as 2005. The TSB covers up too 2008 model years.
The plug ejection thing absolutely can happen on the 4.6 2v, my mom had a 2000 Grand Marquis and it launched twice. The 04(03 Down Under)-mid 08ish 3v ones had the plugs that would break off.
All the intakes, even the "fixed ones" on the 2v engines leak. Fortunately they are easy to change out on a Mustang.
All the intakes, even the "fixed ones" on the 2v engines leak. Fortunately they are easy to change out on a Mustang.
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Originally Posted by OVERKILL
Originally Posted by A_Harman
No, the spark plug thread issue is only on the 3-valve engines.
That's the plugs getting stuck (2-piece) and breaking off issue. The OP is concerned with the plug ejection issue, which was a 2V problem.
You are right, 2 different issues.
Originally Posted by A_Harman
No, the spark plug thread issue is only on the 3-valve engines.
That's the plugs getting stuck (2-piece) and breaking off issue. The OP is concerned with the plug ejection issue, which was a 2V problem.
You are right, 2 different issues.
OVERKILL
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Originally Posted by clinebarger
Originally Posted by OVERKILL
It's my recollection that the plug launch issue was fixed for the '03 model year? My '02 Expedition was definitely affected by it.
Interesting......I have seen it happen on trucks as late as 2005. The TSB covers up too 2008 model years.
My recollection was that they had a revised casting with more threads that I thought was released in '03? I may have the date wrong. I don't believe they were full threaded though, just an increase to like 4 or 5 or from 3? It was later on that they got 8 threads.
Originally Posted by OVERKILL
It's my recollection that the plug launch issue was fixed for the '03 model year? My '02 Expedition was definitely affected by it.
Interesting......I have seen it happen on trucks as late as 2005. The TSB covers up too 2008 model years.
My recollection was that they had a revised casting with more threads that I thought was released in '03? I may have the date wrong. I don't believe they were full threaded though, just an increase to like 4 or 5 or from 3? It was later on that they got 8 threads.
Originally Posted by OVERKILL
Originally Posted by PowerSurge
The plug ejection problems were primarily the 5.4 2v. The stuck plug problems were the 5.4 3v.
The 4.6L, 5.4L and 6.8L all suffered from plug ejection in 2V trim as they all had the 3-thread heads. The truck 5.4L and 6.8L seemed to have more frequent occurrences because they likely experienced longer periods of elevated cylinder pressure.
You missed where I stated "primarily".
Originally Posted by PowerSurge
The plug ejection problems were primarily the 5.4 2v. The stuck plug problems were the 5.4 3v.
The 4.6L, 5.4L and 6.8L all suffered from plug ejection in 2V trim as they all had the 3-thread heads. The truck 5.4L and 6.8L seemed to have more frequent occurrences because they likely experienced longer periods of elevated cylinder pressure.
You missed where I stated "primarily".
I find it funny that a company that has been trading as long as Ford made such a simple mistake. I would look to aftermarket heads with more threads and more CFMs as a permamnent fix for the issue
AZjeff
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Is there a successful permanent fix for this besides new heads? If so should it be done proactively?
OVERKILL
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Originally Posted by PowerSurge
Originally Posted by OVERKILL
Originally Posted by PowerSurge
The plug ejection problems were primarily the 5.4 2v. The stuck plug problems were the 5.4 3v.
The 4.6L, 5.4L and 6.8L all suffered from plug ejection in 2V trim as they all had the 3-thread heads. The truck 5.4L and 6.8L seemed to have more frequent occurrences because they likely experienced longer periods of elevated cylinder pressure.
You missed where I stated "primarily".
Uh huh (no, I didn't miss it). I was just clarifying that it definitely impacted all three engines. I'd expect the 6.8L occurrences were almost or even as frequent as the 5.4L ones, as I know of multiple owners of 6.8's from that period who have had the same issue I had with my 5.4L.
Originally Posted by OVERKILL
Originally Posted by PowerSurge
The plug ejection problems were primarily the 5.4 2v. The stuck plug problems were the 5.4 3v.
The 4.6L, 5.4L and 6.8L all suffered from plug ejection in 2V trim as they all had the 3-thread heads. The truck 5.4L and 6.8L seemed to have more frequent occurrences because they likely experienced longer periods of elevated cylinder pressure.
You missed where I stated "primarily".
Uh huh (no, I didn't miss it). I was just clarifying that it definitely impacted all three engines. I'd expect the 6.8L occurrences were almost or even as frequent as the 5.4L ones, as I know of multiple owners of 6.8's from that period who have had the same issue I had with my 5.4L.
Originally Posted by HM12460
It's a GT, so it has the 4.6 2 valve s.o.h.c. engine factory rated at 260 horsepower. Ford fixed the intake manifold issue for the '02 model year, but I am wondering if the 2003-04 model year with this engine had the spark plug ejection/stripped threads issue? Please comment if you have any knowledge or first hand experience with this.
My Dad went through millions of miles on 2V 4.6L Ford mod motors. Never once did he have an issue with stripped plugs. Of course, millions of miles and a dozen cars is still a pretty small sample size, realistically. I wouldn't stress.
It's a GT, so it has the 4.6 2 valve s.o.h.c. engine factory rated at 260 horsepower. Ford fixed the intake manifold issue for the '02 model year, but I am wondering if the 2003-04 model year with this engine had the spark plug ejection/stripped threads issue? Please comment if you have any knowledge or first hand experience with this.
My Dad went through millions of miles on 2V 4.6L Ford mod motors. Never once did he have an issue with stripped plugs. Of course, millions of miles and a dozen cars is still a pretty small sample size, realistically. I wouldn't stress.
OVERKILL
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Originally Posted by AZjeff
Is there a successful permanent fix for this besides new heads? If so should it be done proactively?
Yes, the Lock-n-Stitch insert kit is the only one officially endorsed by Ford for fixing the threads in-situ and is often performed at the dealership or farmed out. Our local dealer uses a mobile machine shop that comes and installs the kit. I had it done in our Expedition.
Is there a successful permanent fix for this besides new heads? If so should it be done proactively?
Yes, the Lock-n-Stitch insert kit is the only one officially endorsed by Ford for fixing the threads in-situ and is often performed at the dealership or farmed out. Our local dealer uses a mobile machine shop that comes and installs the kit. I had it done in our Expedition.
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