power brake booster

GregoryChristian · Post by **GregoryChristian** » July 25th, 2006, 7:02 am

when braking my pedal goes all the way to the floor and my car feels like is is sliding on the road in the front right corner ....I also notice that I can move the passenger side brake pads with my hand and make them rattle while the drivers side is tight and snug ...I took off the wheel and checked the caliper screws and nothing was loose there is also noise present inside the car when pumping the brakes coming from the firewall area .....any ideas ?

happyclown · Post by **happyclown** » July 25th, 2006, 10:40 am

That’s odd... I've started to notice a similar issue. Only mine is with the drivers side. If a great deal of weight is on the passenger side the pedal will get the mushy feel and I get the feeling a tire is locking up. Yesterday I heard a cracking scraping noise coming from the caliper.

I’m going to start with the basics as well, make sure everything is tightened and where it should be, then bleed and fill the lines. If I were you I'd look for some leaks. Mine doesn't quite lose all pressure. Then scrape off any rust or anything building up that would cause the caliper to stay open.

What kind of noise do you hear? Is your fluid low? Does it get low after pumping them for a while?

GregoryChristian · Post by **GregoryChristian** » July 25th, 2006, 7:30 pm

my fluid level is not low and no leaks are present .....the sgueaking noise comes from underneath the dash when pressing the brake pedal and is very noticeable near the master cylinder under the hood

PATDIESEL · Post by **PATDIESEL** » July 25th, 2006, 10:26 pm

There is a vaccum seal between the booster and the MC that might have a leak. However, I'd start with more common issues like old brake fluid (water or air in the lines). A poor seal on the brake fluid filler cap (letting water vapor in and ruining the hydrolic fluid). Old busted calipers that just aren't functioning properly anymore. Worn down rotors that aren't thick enough for the fully extended caliper to get a good grip on. Old rubber lines that are ballooning when you press the pedal.
Most of the above are easier to replace and see if it fixes it since you will be hard pressed to see the brake line ballooning or the water in the fluid or know if the caliper is pressing with the correct amount of force.
You can have the rotors thickness checked, you can make a visual inspection of the pads for even wear to tell if a caliper is not functioning properly (uneven from left to right side pads or a different thickness from top to bottom or left to ride of the same pad). You can look at the seal on the cap and if it looks bad get a new one or a new seal if you can find just the seal. However, just b/c it looks ok doesn't mean it is making a good seal. Unfortunately there is no way to tell about the cap unless you take the MC off and do a vaccum test on a bench with the line taps blocked.

This should give you a good place to get started. It is not uncommon on an older car. Especially one with more weight than stock and a sporty car that will have the brakes more aggressively used.