Brake pedal problemo!

[SHO&STANG]

I just got the car it is a 1991 SHO with 162,000 mi on it. I was having a problem with the brakes. When you use the brakes the pedal stays depressed about a 1/2 inch and is still aplying slight pressure to the brakes, if you put your foot under the pedal and pull up on it, it no longer applys pressure to the brakes. The guy that sold me the car told me that it was probably that the vacuum line going to the brake booster was clogged and that, that was what the problem was. This didnt seem to me like a clogged vacuum line would have any thing to do with the pedal not returning all the way up. I figured if the power brakes were working then the line couldn't be clogged.

Does any one have any idea what the problem might be, or was this guy right?

 

[Rob94]

Master cylinder is junk. Replace it.

 

[JaySHOguy]

I had the same problem with my first '91 SHO...new Power Brake Booster fixed the problem.


Fun to change

 

[91 SHOplus]

PB Booster.

 

[MO-KAN SHO]

Would this be the likely cause of MY problem, too?

When I first step on the pedal, it seems rather soft, but if I let off and get right back on it (pump it) it grabs nice and tight. I've already got SS braided lines on it, and the calipers all check out okay. Brakes have been bled a couple of times thinking there was air in the lines, too.