something new has come up, maybe...... i thought that the power brake booster when hooked up to the manifold vacuum would create a vacuum inside the booster and not continuously pull air. eg., i disconnected the vac hose from the booster to the engine and sucked on it to see how it worked (sounds wierd, i know), and well, the air just kept coming. is that the way its supposed to work? and yes, i took the check valve out and put the hose directly up to the booster grommet to make sure the leak wasnt coming from the connections.