Spongy Brake Pedal - Any Advice?

[Nitkin]

Hey Guys,

Few weeks ago I was driving my MS3 hard in a 100 degree heat. After about 30 minutes my pedal began sinking to the floor. I thought may be I boiled the fluid and there is some air in the system.

I went the the dealer and they bleeded the system, but the problem did not go away. I went to the dealer again and after 3 mechanics drove it, they all said the brake "feels fine". Well, it doesn't to me. The pedal is very soft and under hard braking it's unpredictable. It's hard to estimate the amount of pressure needed to scrub speed as the pedal sinks deep and the stopping power is inconsistent.

Anybody had something similar?

 

[Kain]

Bleed them yourself. The mechanic probably did a rush job. Typically, you want to start from the caliper furthest away from the master cylinder and work your way towards the front.

 

[J-Villa]

check your pads yo.
flush fluid. Doesn't brake fluid absorb h20 over time or break down. something like that? a flush and new fluid never hurt anything.

 

[okpanic]

You can always swap for the stainless steel brid wrapped brake lines. I've seen this problem in older cars before. The rubber that is used in the brake lines in some cars can stretch under heavy load and high temps. Once it stretches it doesn't go back to normal. So you get the same amount of fluid having to fill a bigger space. SS lines will get rid of that problem. I saw this same problem in my buddy's '92 5.0.