Thread: Downshift???

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  1. #1 Downshift??? 
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    I have an 04 GP GT and when I'm driving and go WOT it will get to 90mph and then just sit there while its at like 6k-7k RPMs. To go over 90 I have to release the gas and then slowly push it past 90 but right when I go WOT when I'm over 90 it downshifts and gets stuck at 90. I'm pretty sure this isn't normal but does anyone have any ideas what is causing this?
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  2. #2 Re: Downshift??? 
    Turbo is the way to go. BillBoost37's Avatar
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    Please confirm that 6-7K rpm. If so, your pcm has something changed in it. This may explain the lack of a shift into the next gear.
    I drink..so consider that when reading my posts.

    2010 Audi A6 Dual IC's
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  3. #3 Re: Downshift??? 
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    It's at about 6200 when it gets stuck. And I have a DHP PCM that I put in about 100 miles ago and since then It now gets stuck at 100mph instead of 90 but it still does the downshift when I go WOT over 100

    Here are some videos of it:
    YouTube - Tranny Stuck
    YouTube - Downshift
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  4. #4 Re: Downshift??? 
    SE Level Member Wakeboy1337's Avatar
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    I would tell them.
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  5. #5 Re: Downshift??? 
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    Well I don't think its the new pcm because it would do the same thing before when I had the stock one except it did it when I hit 90 instead of at 100
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  6. #6 Re: Downshift??? 
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    So... Just to be clear, this happened with your stock pcm and the DHP?

    If so its probably a trans issue. I would say trans pressure???

    Edit: Ninja'd you answered the first part.
    Quote Originally Posted by W-Body Store
    Remember, GM engineers didn't take into account your need for speed.
    Daily Driver: 06 Grand Prix GT / 9.4:1 CR / IS3 Heads / Ported Gen V / ZZP Headers / HPT Pro / Pulleys: 4.25, 3.8, 3.5, 3.4, 3.2, 3.0, 2.9, 2.7
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  7. #7 Re: Downshift??? 
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    How would I go about fixing that. Would I have to take it to a shop or could I do this myself?
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  8. #8 Re: Downshift??? 
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    I would take it to a tranny shop if you don't know transmissions. It could be as simple as a hole in a line or something as complicated as a gear being ground down, but I'd let a pro figure it out.
    Quote Originally Posted by W-Body Store
    Remember, GM engineers didn't take into account your need for speed.
    Daily Driver: 06 Grand Prix GT / 9.4:1 CR / IS3 Heads / Ported Gen V / ZZP Headers / HPT Pro / Pulleys: 4.25, 3.8, 3.5, 3.4, 3.2, 3.0, 2.9, 2.7
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  9. #9 Re: Downshift??? 
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    Ok thanks. Also I had the transmission fluid flushed when I first got the car and it had 134k on it. Could they have messed up or something?
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  10. #10 Re: Downshift??? 
    Turbo is the way to go. BillBoost37's Avatar
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    Since your in Indy.. call up PRJ and go see what he says. Probably toss a better tune on it and fix all the issues.
    I drink..so consider that when reading my posts.

    2010 Audi A6 Dual IC's
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  11. #11 Re: Downshift??? 
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    I'm thinking about doing an HD differential upgrade could that fix this issue?
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  12. #12 Re: Downshift??? 
    The Blue One blueguy's Avatar
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    No...that won't do anything but make the differential stronger.

    It's in the tune...are you sure the PCM was year specific? I bet your car is doing the same thing mine did...mine is an '03 and had to have a year specific PCM since the transmissions are different internally.

    Then again...just to be on the extreme end...what are the mods done to the car? Just a PCM? Other thing might be some CRAZY knock levels.
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  13. #13 Re: Downshift??? 
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    Well I bought the DHP pcm for the 2004 gp. and I dont think it would be the pcm since it did the same thing with the stock pcm but then again I am a noob
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