I need your help guys
 

I have a 2000 stock Mustang GT and I changed out my spark plugs on friday moring along with my idler pulley. When I put everything back together and closed the hood getting ready to go to work , I tried to start the car and a puff of white smoke came from under the hood , and the tailpipes. smells like fuel. I think i made a mistake of sparying compressed gas down in the spark plug hole. is there any fix to my problem. I sprayed the compressed gas in there to get the sand and dirt out. Its also making a loud popping noise.

Did you touch the fuel rails? Turn the key on and check for leaks. Also you said you sprayed compressed gas in the holes. Do you mean air? And did you do this with the plugs in or out. If you think you got something in the engine pull the plugs out and crank the engine over a few times to try and blow it out.

yea I touched it but I didnt remove anything to the fuel rails. I used compressed gas , it was an asshole mistake, I meant to use compressed air. but with me cranking the engine over to blow out the cylinders would it do any damage to the motor?

nah, no worries on the comp air...now as far as the "popping" noise, what/who's plugs and what gap and you may have damaged one of the COP's

I am using bosh platinum 4 plugs and how do I test the coils themselves?