Re: Vacuum Leak?
I'm not sure this will apply to you, but...
Have you checked the selector switch itself? If it's like I think it is,
it'll be a vacuum switch that directs the vacuum to different vacuum motors.
The switch is actually a valve I guess. It rotates as you push the selector
The reason I mention this is that I had the vacuum switch fail in a fan of
mine a few years ago. IIRC, it's actually two plates of plastic that rotate
against each other with a seal between. What happened to mine is that one
of the plates cracked and the two plates separated slightly, releasing the
vacuum pressure. When I went to the boneyard, I noticed that many of these
had been removed already or that they were broken in the same place as mine.
I ended up getting one from the dealer.
I know there are other vacuum leaks that are more likely the source of the
problem, but don't overlook this possibility if you've ruled out others.
"NES" <NES@USA.NET> wrote in message
>I posted this question some time back but lost the replies. Please
> forgive the duplicate request.
> I have a '93 full-size Bronco. I have a problem with the dash vents.
> While accelerating and therefore depleting my vacuum reserve, my A/C
> defaults to blowing through the defrost vents. When I decelerate, the
> vacuum recovers and my A/C goes back to blowing as it should, through
> the dash vents.
> Anyone have any advise as to where to look first for the leak. I've
> already replaced a small vacuum valve/device under the hood to no
> Thank you