Originally Posted by PQ
But the vacuum comes from that end. Wouldn't I need to do that from the other end? And how could I do it. I'd have to get behind the firewall right?
No, the vacuum is generated at the intake manifold/maggie and fed to the booster via the line. You want to crimp it shut at the manifold end to eliminate the booster, line and check valve. If that identifies the prob, then you can work your way down the line to see what component is the prob. Capiche?