Hissing brake pedal

[Twglace]

Hey all!

I have a hissing brake pedal... When I apply brake it goes away.. the previous owner states they were told it need a new brake booster... Anything to check before I start looking for a new assy? Or is there a way to rebuild if it is the issue?

P.s - the brakes do feel very solid


Thanks! Thomas

[gadget73]

see if the booster holds vacuum. If its hissing with the pedal up and not with it down, that sounds like a crack in the diaphragm though. Easy enough to tell with a vac pump.