I have a 1994 Full size blazer, 5.7L automatic.

Just recently, the brke pedal have become hard to push down. It makes a hissing sound when pushing on the pedal. The engine revs then I push all the way down.

Is this a result of a bad power brake booster, a vaccum leak in the booster or something else?

Money is very tight, is it ok to just put up with this for a little while or is this unsafe.?

Any help or suggestions would be appreciated.

 

That would be what I would replace first. Definitely sounds like a blown booster to me.

 

X2 on a bad booster.

Is it unsafe? Depends on how well you can stop without having power brakes. You can get a rebuilt booster at just about any parts store, swapping them out is pretty straight forward. Be happy you have a full size because it is a major PITA on these little 'uns.

 

is it really that bad to replace on 2nd generation 4.3 vortecs cause my brakes act like when i come up to a stop the abs acts like it locks up and it wont stop. wondering if this could be the brake booster also . or something else. whole abs pump assembly?