potatobbq

My car is boosting 10-8-9 and it idles around 1,000 rpm and 16.5-17 mm Hg of vacuum... The idle screw is adjusted as low as the idle will go and my car is a 93 R1 with 38,000 miles on the original motor. Any ideas what's keeping the second turbo from boosting all the way back up to 10 psi and keeping the idle high? The fact that it's "almost" working properly (10-8-10) actually sorta makes it harder to pinpoint the problem, I think it might be a vacuum leak or valve leak somehwere... If anyone has had any experience with this same boost pattern, any suggestions would be appreciated, thanks.