99 CRV AC Problem
 

the AC is not working like before. It will always blow cool air, but sometimes not too cold. For example, if I'm at idle or stop and go traffic, the air isn't as cold, but if I'm driving on the highway at constant speed the air is normal cold. There used to always be slight variations between idle and highway, but now it seems idle is noticeably less cold. Any clues? Thanks.