In my 06 Lbz i had my cruise set at about 120kph (75 mph) and threw an engine code, codes P0401 and P0301, egr inssufficcent and cylinder A missfire. Ive got Airaid cold air intake, 4" turbo back and BD X-tuner, ive thrown P0401 before but never the other. Im going to block and finger this summer to get rid of the egr codes. would a missfire have anything to do with EGR?

any ideas about this anyone?

has anyone else ever even got a missfire code? any opinions on this would be much apprecited, i just want to know what direction i should be putting my investments towards