Engine Suspicious Spark Plug Scenario

Discussion in '1994 - 1995 Specific Tech' started by joetrainer31, Apr 2, 2013.

  1. joetrainer31

    joetrainer31 Member

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    So I'm lighting up the message boards with some perplexing issues concerning a new to me 95 GT. One issue I have come across is a hesitation/stuttering/lethargy to the car. While checking out the ignition system components I observed that the cap/rotor seemed (not stock), but new. I replaced the plug wires, and was going to install basic autolite 25's when I noticed that they would not screw into the heads. Maybe it was my mishandling? Anyhow, the car currently has Champion RS14YC6 plugs. The Champion plugs have a much longer thread length than the Autolite 25's. I have 3 questions:

    1. Could these be the wrong plugs?
    2. Any clue why the Autolite 25's do not seem to screw into the heads?
    3. What, if anything, am I missing?
     
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  2. gearheadboy

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  3. gearheadboy

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    They actually fit a Cobra that year. Are your plugs angled or straight out?
     
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  4. joetrainer31

    joetrainer31 Member

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    My plugs are angled now that you mention it. I'm quite perplexed over what the issue is. How do I check the heads w/o taking the thing apart? Would there be casting numbers visable? I have never owned a 5.0 that will not accept Autolite 25's or equivalent.
     
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  5. RsStanG1987

    RsStanG1987 I shaved all my pubes playing this game.

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    Maybe he has gt40 heads


    Yellow Bear racing 2k13
     
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  6. joetrainer31

    joetrainer31 Member

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    The thought crossed my mind because of the plug fit issue & because there is also an SVO intake manifold, and cobra tail wing. This mistery is killing me because the car runs like crap.

    I did a basic KOEO run and the only code I got was for the fan, which demonstrated 2 speeds anyhow (clearing ECM now in case it was stored). I also did a KOER basic test and everything came back good. I then did a Cylinder head test and it scored perfect. I changed the fuel filter 1st thing & did a basic tune up.

    I could sure use some wisdom/advice on the matter. And, what is "Yellow Bear racing 2k13"?
     
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  7. gearheadboy

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    GT40P heads have a different angle than GT40/Cobra/Standard 5.0 heads.
    [​IMG][​IMG]
     
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  8. gearheadboy

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    Pictures?
     
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  9. joetrainer31

    joetrainer31 Member

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    Beautiful pictures! So helpful -thank you. The spark plug angle on the heads looks a lot more swept like the "GT" picture, but I will return once again to the car in order to check for a casting.

    Side note: Even after clearing the ecm (battery unhooked 30min) I'm still popping a code 564 (fan control circuit failure) even though the fan demonstrates 2 speeds. I wonder if this somehow plays into the mix.

    Question: should I look toward the front or rear of the head in order to observe the cast markings?
     
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  10. joetrainer31

    joetrainer31 Member

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    Ok, On the passenger side head (front) it says "GT". On the driver side (front) it says "22".
     
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  11. RsStanG1987

    RsStanG1987 I shaved all my pubes playing this game.

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    I think the fan code can come from the CCRM being bad but I'm not to sure


    Yellow Bear racing 2k13
     
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  12. gearheadboy

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    It sounds like you have GT 40 or Cobra heads. NOT GT40"P". That explains the spark plugs. The heads are the same L or R. The GT casting is in the rear on the other head. I have no idea on the code. Maybe google it.
     
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  13. joetrainer31

    joetrainer31 Member

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    Gearheadboy,

    I went with your prior instructions/information and bought plugs to fit GT40 iron heads (i.e. 764's). I have not tried to install them yet because I was busy addressing a 411 & 412 code by cleaning out the IAC, fixing its 2 exposed wires, and making sure it was properly secured to the TB -which it was not =vacuum leak.

    Anyhow, you pictures and advice were invaluable! Thank you so much. Now I need to try and address the CCRM. I have a coolant fan circuit fail code. The fan displays 2 speeds w/a KOEO diagnostic, but for some reason it pops the 564 code. I'll take any thoughts you want to give, I have plenty of thoughts about the whole CCRM thing myself!
     
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  14. gearheadboy

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    You are quite welcome. Please keep frequenting our forums. You can yourself be of help to someone. I'll do some research this evening and get back to you.
     
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  15. joetrainer31

    joetrainer31 Member

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    Thanks again gearhead. I'd be glad to help anyone that has need.

    I plan on pulling the CCRM today in order to get a part # and visual. I hear/read that when replacing the unit one needs to get the exact same one (e.g. part #, color of box, same large single letter code "R" or "S"). I'm anticipating your research results!
     
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  16. joetrainer31

    joetrainer31 Member

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    Behold, the dreaded CCRM hath been pulled from mine car.

    image.jpg
     
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  17. RsStanG1987

    RsStanG1987 I shaved all my pubes playing this game.

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    Idk if its the problem.. Mine went and caused all sorts of codes


    Yellow Bear racing 2k13
     
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  18. joetrainer31

    joetrainer31 Member

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    I'm assuming that its at least "a" problem due to the code that I pulled. It lead me straight to the CCRM. I purchased another one with exact part number and "R" code as my current (it all must match up to function properly). A friend of mine works on electronics for a living. When he gets some time he will completely overhaul my old one. Then I'll either have a spare or one to sell on ebay.
     
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  19. RsStanG1987

    RsStanG1987 I shaved all my pubes playing this game.

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    I diddnt know u had to match them I used a gt one on my cobra and had no issues


    Yellow Bear racing 2k13
     
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  20. joetrainer31

    joetrainer31 Member

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    Maybe you were fortunate? I did a bit of research that indicated that the part is used in several models, but that it must be matched exactly. Moreover, the rebuilder I bought it from only warranties it and commits to its proper function if you buy the exact part.

    I could simply be wrong, but I didn't want to take the chance. Nonetheless, i'm glad that your replacement is working for you. I don't like electrical problems! lol
     
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