I just got done doing my full tune up on my d15 with mpfi swap. The cars idle is set at 750 and the timing is set at 18degress. I have never checked vacuum on it before but I did today and the gauge read 27inches at idle. During my tune up I noticed my cat is starting to come apart because it rattles when you tap on it, this may be my bad fuel milage concern, but when I saw the high vacuum that blew me away. I have been a tech foot over 7 years and I have never seen that before. I will say that both the throttle blade stop and the idle adjustment screws have been messed with. Any ideas? Is the throttle blade supose to be completely shut at idle? If not what's the stock setting?