Vaccum problem

[Keith240]

I have an S13 with a blacktop SR20 in it and it had usually pulled 20-21 Hg of vaccum up until recently. Now it varies anywhere from 16-19 at idle and it will randomly change as I am driving. It feels like the car runs alot better when it pulls more vaccum, what could be causing the flucuation in the vaccum? And is it something I should be concerned about? Thanks.

[redsuns3838]

could be a simple leak... first thing is to check all the vacume lines and IC piping for leaks. best bet is to , line by line, cover them in water and check for any bubbles when you open the throttle. someone once recomended using soap and water. you could try that if you want.