vacuum problems??????????

everytime i stop at a light with my max a/c on high,my engine looses idle and cuts off,but if its on regular a/c it will stay at about 1 grand rpm and go up to about 1500 rpm and back down to 1 grand rpm,whats the problem?:rolleyes:

never mind i found out the problem . there is a thingie missing on the throttle body , ? i was looking at it myself and my friend noticed that there was something missing , so i said "i dont think so" turns out there was something misssing , what it is , ? , mystery to be solved.

so if there are any suggestions on what this could have been,anything would help , for now i'll have to live with it , rig it , or find the part .:banghead: :shakehead :shakehead :eek: