okay so last night i was doing prob about 115mph and my civic (4speed auto) was in 3rd gear, it shifts at 6600 and redlines at 7200, welll when i got to 7200 rpm that was about 115 and my car jolted back hard, so as i slowed down and floored it again it bogged really bad, and usually when im rolling in neutral and i rev it it revs up to 7200, well now it only revs to 5500 and wont engage vtec even when i floor it, i know i was stupid but i need help to see if i blew a piston or something.

 

Check for dead cylinders by disconnecting the fuel injectors one at a time with the engine idling. Sudden decrease in performance with no CEL is also often because the timing belt has skipped time.

 

but you see my check engine light has been on for idle speed control and manifold control vehicle speed, so like i would have to check my diagnostics again to see if something else is added, other threads said that the vtec soleniod can overheat too, causing the problem

 

Check and see what CEL codes you have now. Then reset and see which ones come back.