Im scared to even ask this, but sometimes when i've been driving for a bit and i put it to the floor and start hitting 6k+ rpm the engine loses power and makes a very loud noise, similar to it misfiring from coils (I know its not that). Im a little nervous to drive it incase its an apex seal but could it be anything else? its almost like a high pitched fast knocking that it super loud. sounds like there is a hole in the exhast right by the engine, but it only does it when its "slipping".... anyone had this problem before or anyone know what it is? i was looking to sell and ofcourse it started just after i put the car for sale...
thanks

 

unless your in the wrong section, shouldnt your car be under warranty, now to help you it might be your coils

 

what year and what millage?