Always start with a scan that's number one. It will tell you exactly what is wrong..
2003 Grand Prix GTP-3.5 setup, sold it, miss it
2002 Grand Prix GT-top swap, GT1 Cam, SD Headers, 90# springs, 42.5 injectors, 3.4 pulley - sold
2012 Chevrolet Cruze LTZ-Summit White, 1.4Turbo