Hi,
It’s hard to say without seeing all of your code, but obious things to check is if player pawn at index 0 is indeed a AVehicle (derived from APawn), and I assume that PowerLevel is just an int32 (i.e. not a pointer).
PS! When the engine crashes you usually get a call stack dump, and if so then it’s a good idea to post the whole thing as that access violation doesn’t tell us much - except that there was an access violation 