Results 1 to 2 of 2

Thread: 4L80E TCC Locking When It Shouldnt And Other Odd Shift Behavior

  1. #1
    Tuner in Training
    Join Date
    Sep 2013
    Posts
    19

    4L80E TCC Locking When It Shouldnt And Other Odd Shift Behavior

    Need Help! TCC and transmission shifting issue. Currently my torque converter is locking up when it shouldn't be. It locks up at low speeds (less than 50mph) even though the tables have it coming on at 76mph. It pretty much engages as soon as it shifts to 4th. Also, with the gear selector in 2 or 1 it wont downshift until 20MPH or less even though it is setup to down shift at 71MPH or 46MPH. Everything was working great until I maxed out the tables for when the TCC applies so that I could do some part throttle tuning without it engaging. I changed everything back to where it was but it seems like its operating off of a stock table rather than the ones I have been changing. I've attached the tune and a log file. Any help is much appreciated. Thanks!
    TCC Engaging Wrong.hptTCC Engaging Wrong.hpl

  2. #2
    Tuner in Training
    Join Date
    Sep 2013
    Posts
    19
    Also, if I leave the shifter in 4th, everything shifts down and up more or less normally. It goes down to 1 like it should at a stop and runs up through the gears like it should from acceleration. It just isn't referencing the right values for manual gears changing it seems. With the gear shifter in 4th it still has problems with the TCC locking up at the wrong times.