So recently had my serpentine belt break. With my infinite good luck a piece got through the timing belt cover and got wrapped around the crank. By the time i found that that the timing mark was 180 off tdc. But could have spun more than that while i was trying to start the car after the serpentine belt change. After setting the time its still not starting. Triple checked all my marks and all the pins go in as the procedure states so pretty sure im good there. However, there is pretty much constant blowback out of my intake when cranking over. I'm guessing my valves and pistons may have had their first kiss. Thoughts or ways to confirm? I'm a mechanic by trade just not the automotive variety. Learning as i go with this adventure lol.