Vacuum Booster Noise

[geunther]

Working on my brakes to get them up to snuff. My vacuum booster seems to hold vacuum. After it sits a minute to two I can pull the vacuum line and it pops like it should. However, when I press on the pedal I can hear air rush past the robber boot at the rear and where the rod goes in. Is this normal or an indication of something wrong.

Obviously the boot needs replaced, so not sure if that is related.

[davepl]

A more educated opinion should be by soon enough, but until then I'll note that there's an air filter in there (a piece of foam, not fancy, but that's what it does) so air would appear to be intended to flow through there.

[dwcsr]

The air baffle is probably disintegrated, Air should be applied to the back side of the booster diaphragm through a valve when you push the pedal. When the baffle is gone you hear the whoosh noise.

[midniteblues]

i just did one on a 95 a few weeks ago. that one would do the usual whoosh but as you would hold the pedal down it would continue hissing/whooshing. more like a "shhhhhh" yhea thats how it went vaccum exscaping

the booster still worked but pedal was very slow to return.

so yes they will make a whoosh sound but any more sound following that usually means the booster is going out.

[dwcsr]

if it continues to whoosh it worn out