wyawoo

I have a 96 civic lx that I recently blew up. I put a new motor in it and everything worked when I turned it on. Bug when I go to put it in drive the d4 lights starts flashing. The reverse seems to have more power than drive. When I put it in drive and try and take off its like the car won't pull itself and everthing is hooked up right. I have checked probably 10 times. Need help!!!