'05 Colorado code questions....

I have a '05 5 cylinder Colorado. It just failed inspection for these codes....
P0506: idle control system rpm lower than expected.
P0106: manifold absolute pressure/barometric press circuit Rng/perfrm Pbl

Can someone tell me what may be causing these codes and how to fix them?
thank you......

clean the throttle body bore. there is a bulletin for this issue.On rare occasions, a SES light may be experienced due to DTCs P0105, P0106, and/or P0506. There may or may not be an idle complaint accompanying the SES light. This may be due to excessive carbon build up in the throttle body.