The shut off valve goes off when the mightyvac has two pumps for sure and sometimes one. That leads me to believe the shut off valve is good. At the same time the vacuum coming from the ignition switch seems fine when tested separately too. If I do have a vacuum leak with the ignition switch where would I look? None of the vacuum diagrams I have found show one for the ignition switch. Is it connected directly to the key switch or does it go over to the ACC area?