what does it mean, how do i correct it?
Fault Code P1415, secondary air injection sys malfunction, left bank on 2001 Chevrolet Tahoe
replace the check valve.
in the morning, your air pump works for about 15 seconds to burn unburnt fuel when the engine is cold. it may or may not be working. a shop with a scan tool can test the pump and check valve for proper operation and determine the failure. a guess can be very expensive. i would get an expert opinion.