1990 Buick Park Avenue Brake Issue

[The Critic]

I'm posting this for a buddy of mine.

1990 Buick Park Avenue, with ABS.

The brake pedal has a bit of freeplay, but then, the brake pedal feels very hard. The brakes still work, but in order to stop, you have to push the pedal VERY hard. In addition, you have to push the pedal to the floor before it will begin to stop.

The fluid level is full. If you pump the pedal several times, hold it, and start the car, there's no movement of the pedal.

Is it the booster?

Thanks.

 

[VK56VD]

Maybe the brake cylinder. Have you tried flushing/bleeding the system?

 

[T-Keith]

Check out these posts:

http://lesabret.com/phpBB/viewtopic.php?f=13&t=6374&p=43815&hilit=ABS+hard+pedal#p43815
http://lesabret.com/phpBB/viewtopic.php?f=1&t=4059&p=27857&hilit=ABS+hard+pedal#p27857

 

[Mr_Incredible]

I had this problem on my truck. I didn't use it very often and the rotors would rust. Eventually, the pads and rotors became glazed over and very inefficient.

New pads with with a bedding agent on them fixed it. Next time I won't bother getting new pads, I'll just take off the rotors and rough them up real good, along with the pads' surface.

 

[Schmoe]

Check the back breaks. On mine, they were drums and the master cylinder was leaking.

 

[mechtech2]

A bad booster [the big vacuum cannister] may be the problem.

 

[artificialist]

Does the engine run poorly? Chances are instead of drawing in vacuum to boost braking power, the engine is simply pulling extra air in from somewhere.

Maybe if you are lucky, just replacing the vacuum hose and check valve at the power booster will solve this. If not, get ready for a replacement booster.

Sometimes a master cylinder leaks from the back, causing fluid to enter the vacuum booster, and then the vacuum booster fails. ALWAYS check for this if you have to replace the vacuum booster. If you don't, your replacement part will quickly fail, and the warranty is void in this situation.