question for auto mechanics...

[OUTLAW]

I have a '97 chevy truck, 2wd ext cab. Every time I push on my brakes I hear the sound of air releasing from someplace by my pedal. It releases the whole time I put pressure on the pedal and it seems to affect my braking and posibly the idle of my truck. Maybe like some type of vaccum leak or something. any ideas and how difficult is it to fix?

thanks

[croxt]

sounds like the booster has a leak. lift the hood and look at the big round thing behind the master cylinder. been years since i worked on one but if i remember correctly, it has a vacuum line (metal one) that comes off the back of the carb plate or intake.....not sure where. it takes vacuum from the engine to assist in braking.

is the sound worse with the hood up? or is the sound more prevalint in the cab?

[mj1956]

I agree with Croxt, sounds like a bad booster or the vaccuum line is disconnected. Most of the time if the booster is bad the brake pedal will be very hard and the truck will be hard to stop. Sometimes the mastercylinder will be bad or going bad and leak brake fluid into the booster, causing the booster to go out. It is safe to get a rebuilt booster, but I would not get a rebuilt MasterCylinder, save yourself some time and frustration.

[Ole Bill]

just talked to a friend who is lic. auto mechanic with his own business he suggests going to the vacuum booster and check for a bad connection or line between the intake manifold and the booster. it is also advisable to take it to a reputable and certified brake tech to see if the booster itself has a ruptured diafram inside of it this to could cause the noise you hear sounds like your right on the mark croxt

[mj1956]

There is a Brake Check on HWY 59 in Humble just past 1960 going north on the feeder. They will do a free inspection.

[john]

Ck for a leak in the hose and possibly any vacume t's.If its affecting the brakes and making a very hard pedal you got a bad brk booster(vacume).That should be easy to replace.Most come with a master cylinder or you can take a chance at pic a part.

[Gentleben]

Pull de brake booster out and replace it!! Nothing to it ,less you got a leaking shoe :grrr:

[reedlv]

Check with the parts house but most parts houses will not warranty the new brake booster unless you replace the booster and the master cylinder. Alot of times the brake boosters fails because of a leaking master cylinder. The break fluid makes the booster diapham weak and causes it to fail. If the brake master cylinder is replaced. The air will have to blead out of the system or the pedal will be soft and the braking will be poor.

[OUTLAW]

thanks guys