the engine heats up when ideling with ac on on 2004 GMC Savana 1500

turn ac off and it cools down

Asked by for the 2004 GMC Savana 1500
See if there is an electric booster fan that may not working.
1 more answer
Need to check fan clutch operation. The clutch controls fan blade speed. If the fan cluch has failed it will cause the symtom you discribe.