Turning off issues

this question has been posted here before but but haven't been to replied to
my r32 GTR bogs and turns off on me at the most random times
one guy on here said he fixed it by replacing the power transistor which i will check tomorrow morning
but any one else suggest any other problems it could be and on how to fix or price on replacing
I live in the states so sourcing parts sucks
and I have a track day next weekend so Its gonna suck if i can't get fixed before
thanks

does it restart right away or do you have to let it cool down for a while first?