i have a 2000 grand prix gtp 3800 series 2 supercharged. replaced the valve covers and gaskets, i removed the fuel rail and now the car wont start. its turning over but wont kick on. plugs and wires are new. i noticed plugs smell like gas. i cleaned plugs changed oil and it started but once but ran rough and i turned it off was unable to start again. the plugs smelled like gas again. i figured a injector was leaking? but not sure. i took to a shop and hes saying it could be a crank sensor or cam sensor. my question is do u think that could be the problem because all i remove was the fuel rail and before it was running fine. could some how during removing the rail and injectors cause the cam or crank sensor to go bad? he said something about theres juice to the injectors but the grounds dead? just kinda lost. need input / advice. thanks in advance.