First off this is my first post and all the feedback is greatly appreciated. The problem is when I put the car in 1st gear and go its very sluggish almost as if its starting out in 2nd. After that it rides fine. When I drop it down to low gear manually the initial go is alot better but I'll shift up once and nothing still rides out without a shift then I'll shift it up again and it catches. I bought the car with a bad transmission. I bought a used 4l60e put it in and now this is my problem? I was told it could be the ECU being that its a electric shift trans. Could that be a possibility? What should I do?