99 GT spits OEM plug

[trinity_gt]

Heh. A friend's 99 GT is at the dealership having plug threads fixed after blowing out a sparkplug. The car has 120,000KMs (75,000 miles), is going on 7 years old and still has the factory plugs (he bought the thing new...)

As far as he knows the plugs have never been out of the heads. Why would it choose now, so far along in terms of time and miles, before deciding to do this?

 

[Mustang5L5]

common problem with 99+ with PI heads.

It's just that ford didn't put enough threads on the spark plug bung. After years or wear and vibration, they just let go.

 

[trinity_gt]

Yes, I knew about the problem but had sort of assumed it was largely due to folks replacing their plugs and not torquing them correctly. I can't recall when I might have heard of an older car with the factory-installed plugs spewing one after so long and so many miles.

I guess it must be, as you say, just vibration that causes them to back out.

 

[03ghoststang]

yeah they are a problem with the 99+ heads but for some reason people say that the 04's dont have that problem due to having more threads

 

[squares98]

yeah they are a problem with the 99+ heads but for some reason people say that the 04's dont have that problem due to having more threads

That works for me, I hope its true

 

[Mustang5L5]

Not so.

I know of one 2004 Gt that spit out a factory plug

 

[03ghoststang]

Not so.

I know of one 2004 Gt that spit out a factory plug

wow really hmmmm...... we should wait for svttech to chime in or something he will know for sure

 

[sgarlic]

As everybody in this thread has said already, yes, the PI heads are known to have plug blowout issues.

And having been sitting in there for 75,000 miles, probably never having been checked, I can't say I'm surprised in this case.

 

[VPStang]

didn't they also change the recommended plug to make up for the poorly threaded heads...?

and yes-I'd also like to know about the 04 heads

 

[ADRENLN]

wonder how this effects ported pi heads from the big names like mph, fox, and whoever else.

i assume the heads are already threaded when they get them...but it would be nice if they threaded them on their own from scratch.

for all the money i paid i would be so pissed off but truth be told, ive been worried about this since i got them.

 

[ADRENLN]

these are things that you should not have to worry about. such an expensive part too. if there was known problems of somthing cheap shorting out every once in a while, that could be understandable, but these gts are getting really sad. tranny problems, head problems, hot start issues, intake cracking problems.

these are expensive problems that ford should have rectified a long time ago. its enough for me to just give up and get different brand of car. i love my gt and wanted to get it blown but i dont want the hassel of all these expensive probs. i know all brands have their problems, but are they as expensive and does the company just not give a crap?

 

[Kilgore Trout]

Yes the plug was changed, the old series was AGSF the new series (with more threads) is AWSF.

 

[Shiroelex]

common problem with 99+ with PI heads.

It's just that ford didn't put enough threads on the spark plug bung. After years or wear and vibration, they just let go.

Wish the years of wear would help some of these front suspension bolts just 'let go'. It seems like everything else on the car vibrates permanently in place with age. I snapped a bolt off when doing my rear springs, and my 1,000 ft/lb impact gun couldn't bust free the pinch bolt in the front.

 

[Mike97gt]

this has been a problem for a long time on these heads.

as far as how many threads the spark plug holes have. Well supposedly the 2004 2v's have a full threaded spark plug hole. I have yet to count the threads on one of them. I did speak to the tech hotline once about this and the engineer insisted that ALL 2002 and up modular motors are fully threaded.

next time we have a head off I am going to have to count the threads.

 

[Mustang5L5]

2002+????



That's good i guess as i've been putting off a plug change in fear of popping a plug out.

 

[Mustang5L5]

wow really hmmmm...... we should wait for svttech to chime in or something he will know for sure

My mistake, his car was an '00. He was driving his dad's '04 the last time i saw it so i thought it was his.

 

[Dorsai]

I thought the issue was with the short threaded plug not the heads themselves. With Ford specing the longer threaded plug it was supposed to use all of the available threads on the head Anyway I plan to check mine the next sunny wekend that I have nothing to do....