The clutch inside your AC compressor is seized.. or about to take a [censored]. As it wears, it engages quicker (like if you are sitting at a stop sign and you just let off the clutch pedal quickly and stall the car out.) Time for a new AC Compressor.

2006 Pontiac G6 3900SFI GTP Coupe CAI, Stainless Cat Back, Vector Tune, Strut Brace, Eibach Pro Kit, Custom Made Projector Headlights, 4300K, 20% Tint Former Owner- 2000 "Stryped" CSVT CEG Dragon Run- Oct 13-15