Ill log in when I remember my password. til then I have a problem I hope someone can offer msome advice on. I have a 99 Chevy Suburban with soft brakes that makes a ssssssshhhh air escaping noise which sounds like it comes from under the brake peddal. I have plenty of fluid, no apparent leaks and vacuum hose seems solid into the booster. One weird thing, when I apply the brake idling in park, the engine rpm increases slightly(100rpm) and seems to cut out (miss some)? any ideas?