help dont know the problem

[ae86boy]

ok guys i have my xmod 370z with the 2s lipo and gpm parts and locked diff with a problem.....first the motor has been got extremly hot and smeltnlike smoke with a heatsink...so i let it sit for about 2 days and now when i went to use again there was only reverse and steering and the car wouldnt move foward i tried different motors and everythimg...is this a board problem or is my diff not catching?????plz help!!! btw board is a stock street