What's up?,

I'll tell you what's up; I got my ac fixed/converted to R134 this summer. It cools just fine. The problem I'm having is that every time I accelerate/get into boost, the vents divert to the floor and the panel vents go dead; rough in the Texas heat. It's annoying.

Here is what I've done to address the problem:

Read the faq:it mentions replacing the one way check valve(s) at the mani. My car has one check valve. I have tested it and it holds vacuum when I suck/blow air through it. Is this a sufficient test?

I replaced the hose that connects to the manifold and check valve.

The vents still divert under boost.

Anyone have any idea of what my next step should be?

Josh

You have a vacuum leak in the system, whether it be an interior hose or servo motor, , in the engine compartment, or at the vacuum reservoir.

I had the same problem on my 1987 745T. There are two nipples on the vaccuum reservor behind the front bumper. On nipple has a hose on it connecting it to the vacuum system, and the other has as rubber cap on it. The rubber cap had split. One new rubber cap, and the system has functioned perfectly for several years.

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john

Look at the 960 instructions regarding failing air door vacuum motors: you may have this problem.