thanks steve. the reason i posed this question is because there is sprited discussion on the subject in other forums.
the consensus is if needle not pegged minimum at park, it signifies vacuum leak.
my car readings as follows:
Park/Nuetral - 1/8 off minimum
In gear - 1/4 off
In gear,a/c on - 1/2 off
are these acceptable readings? do i have to check for vacuum leaks? where do i start?