Possible engine failure

[ltaudio]

I took the 2001 986 S out for a ride yesterday and it ran fine all day long, on the way home I got some funny behavior on the way home. It felt like I was pulling out in second gear when I would lug it down and started lighting up the sel. I got home and plugged in the comp and it had 6 codes, One code being multiple cylinder misfire detected and individual misfire on cyl2 cyl3 cyl4 cyl5 cyl6. I assumed that it was either a spark or fuel issue. Changed the fuel filter and started it, started up, ran a little rough, I give it a little bit of throttle to see if it would balance out, maby a blip of 4k or 5k and it had a sudden rapping. I turned it off immediately, upon trying to restart the starter wont turn it over at all. I opened the shroud behind the seats, took off the serp belt and checked all the accessories, they all spin fine. I put a mark on the crank pully and put a wrench on it and spun the motor, it spins one 360 rev and stops dead and the same the other way. I at this point am thinking maybe swallowed valve but I am not sure, just doesn't add up to the fact that I drove it running a little rough for 10 miles and it ran fine and then failure.