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Thread: 2000 C5 Vette getting Reduced Engine Power after changing a bad tune

  1. #1
    Tuner in Training
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    2000 C5 Vette getting Reduced Engine Power after changing a bad tune

    Hello

    I put another engine in my Corvette. A rebuilt LS6 Block, LS6 intake, TR224 , 243 heads. Car is stock with everything connected, MAF, EGR, etc... It is auto, with 3:15 gears.

    The car started up and ran good when cold but did not want to idle when warmed up. I drove it around 5 miles. I then had a mail order tune put on it and it would not start. I sent it back and he redid the tune and when I got it back it still would run. It would start and die.

    I then purchased HP Tuners for the closest tuner is and hour away and could not get to it for a couple of months and wanted 700.00 to do it.

    Well I put a new tune on the car and it starts with reduced engine power and I have to keep my foot on the pedal for it to stay running. I am enclosing the tune and log.

    If you can help me I would appreciate it.

    2000YellowC5b9.hpt2000YellowC5b1.hpl

  2. #2
    Tuner in Training
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    Anyone?

  3. #3
    Tuner in Training Turbo-Geist's Avatar
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    What codes are you getting?

  4. #4
    Tuner in Training
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    I will post them when I get home.

  5. #5
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    Here are the codes.

    PCM P1638 HC
    TCS U1255 HC
    BCM U1255 HC
    SDM U1000 HC
    SDM U1016 HC
    RFA U1016 HC


  6. #6
    Tuner in Training
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    Here is a new log file. It is running up to about 2k, but not idling.

    2000YellowC5b2.hpl

  7. #7
    Tuner in Training
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    One more thing. I had to replace the PCM . After I tried to rewrite over the Mail Order Tune the horn relay started clicking and you could not even read the PCM or write to it. So I ordered another PCM with my VIN and did the relearn.

  8. #8
    Senior Tuner
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    Reduced power fault mode I think comes from disagreements
    between alpha-N, speed density, MAF airflow mode and maybe
    on DBW vehicles, between desired and actual throttle position.
    "Bad tune" might have butchered the VE table to where it does
    not match the other airflow modes, or something. Your primary
    VE table sure looks ugly to me, and I think our motors are pretty
    similar (throttle aside) in build.

    But I don't know nuthin' from drive-by-wire and how it likes
    to fail, really.

  9. #9
    Tuner in Training
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    Thanks for responding jimmyblue. I am working on another tune for it now. When I put it on I will post if I got it fixed.

  10. #10
    Tuner in Training
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    Well it works.

    I copied the tune on my wife's corvette which is just like my car. Same heads and intake. The cam is a 218 to my 224 but it has a 585 lift and mine has a 563 lift. Her car was dyno tuned in 2008 and it runs good. The tune works good on my car it runs good now. I will fine tune it when I see how it does.


    Attached is the tune I used.

    c5yellowA.hpt