holy crap people are dumb!

another example taken from the April issue of Import Tuner:

Hey guys, ive got a '98 Audi 1.8T that i wanted to get more performance from and was recomended to port and polish the intake and exhaust. i did a little research and found out abrasive material is used to do it alot of times-like gritty sand. so i got with my friend who tunes hondas and we decided to try it ourselves. we got a bag of sandblasting sand and hooked it up to the intake of the car and started it up. we wanted to let the engine suck in the sand through the intake so it would port it out then push it out the exhaust so it would port the exhaust manifold. i was worried that it might cause problems, but my friend told me it would be ok as long as we didnt make boost and it get sucked into the turbo. after letting the car suck in about half a bag of sand, the check engine light came on and the engine started bucking and kicking and sounding really wierd. we stopped and hooked the car back up normal and took off the sand supply. we tried to start it again and it was really hard. once started it couldnt idle and kept making wierd noises. we took it out and drove it and it started to make scraping and knocking noises. Help! Can anyone tell me what to do! My buddy only does hondas so he dosent know much about Audis.