95 c36 vaccum pump and a/c
 

i'm noticing the vacuum pump in the trunk keeps goin on and off when i have the a/c on. is this normal or is there some kind of leak? also the two center vents on the dash don't blow as much. are these 2 problems related. any help is well appreciated.

IN most cases (99% of the time) they are related! A leak in the A/C system causes the central locking pump to run for a few seconds to help with (MVA).

With the a/c control on AUTO set around 70-72..try pressing the EC button..if that slows the cycling of the vacuum pump then the fresh air vacuum element is the most likely problem..