I figure the Brake Booster is going bad, but wanted to confirm. If you lightly press the pushrod sideways with the MC out of the way, all the vacuum leaks out. Is that a sign it's going bad, or is does the MC housing ALSO provide a vacuum seal ??

This all started AFTER I swapped a new MC on. Typical where the pedal is nice and firm while the car is off, but crank the car and the pedal sinks too far. Also low speed stops require excessive pedal pressure. I suppose I could be "bottoming out" the booster, but is it even worth messing with the booster's "adjustment bolt" if it leaks like mentioned above? ~160K miles on the booster.

Thanks

-- Clayton
Atlanta, GA