More than likely the roller clutch is not holding and when it releases you are left in 1st gear, when it holds you get second. I don't know why so many people wnat to manually shift this transmission. If it doesn't shift the way ou want it to talk to a tuner, manual selection is only useful for holding range, not correcting shift patterns. For example in trucks when towing going down a big hill with a curve using manual second is easier on the truck than riding the brakes for all they are worth.
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