i have a cobalt ss 2007 supercharger LSJ 2.0L .... the car start and die automaticaly when i try 20 time to start the car now i stay started but the rpm idle rev jump to 500 to 3000 black smoke im not able to drive the car ..even in the yard.. and the only code i have is P0300 random missfire of course spark plug is good coil is good gaz pump is good any idee ?? what can cause that ??

 

You tried 20 times to start the car at the same time? Yeah, don't do that. The black smoke is you flooding the engine with gas and it igniting some of it.

 

thank but this is not going to help me

 

problem was the mass air flow