I was wanting to test how my brake booster was operating, but I am unsure as to what values to test it. What I mean is, what should the gauged value of the vacuum be with the engine running? If I pulled a vacuum on the booster (I have a tool to do this), what should I bring it to and how long should I expect to see it maintain that value? What is the proper method to test the check valve operation? If someone could let me know, I would really appreciate it. Thanks, Sean Howley VIN#2345 [Non-text portions of this message have been removed]