Originally Posted by
joecar
I'm not sure about P0100 and P0400, these might be related to MAF and EGR respectively (does not make sense, the C7 Z06 does not have EGR...?).
P0420 and P0430 are catalyst reduced efficiency, however I heard that there may be a GM TSB regarding these (TSB says to flash a new calibration into ECM), altho I don't think it applies to C7. P0420/P0430 are from running a test that manipulates EQR and measures response time from front O2 to rear O2, if it is too short then the test fails.
I don't follow what you're saying...