Car is 1989 260E.
A/C is normally as cold as it can be. However, when engine vaccum drops to near 0 (ex: while accelerating hard), very hot air would come out of all vents. When vaccum returns to normal, cold air is back.
This certainly has to do with some malfunction of some traps in the system. (vaccum actuated)
What should I be looking at and where. Thanks
JackD

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