ET888 your problem might lie within the check valve on the right side of the engine (Bank 2).
I am currently having the monitor not resetting problem too.
Going to take on a little more lengthy drive. I have cleaned the 02 sensors, maf sensor, new cats, cleaned egr valve, cleaned all air pump components, replaced bank 2 check valve bank 1 was holding pressure so didn't feel the need to change it. truck runs great and pump only comes on for about 45 seconds but pumps very well and you can feel it sucking the air into the pump. mine too says atmosphere on the scanner. still not sure what that means but will update after lengthy test drive.
