Join Date: Aug 2007
Location: Fort Worth, Texas
Mushy Brake Pedal
While at the track (first outing in 2019), my brake pedal began to go deeper in the stroke and approached the firewall. Iíve done the obligatory flush (5 liters of DOT4 using GM Tech2) which allowed me to complete one day of a two day autocross. I have replaced master cylinder TWICE with no improvement. I purchased a rebuilt booster only to have my favored garage tell me the booster, check valve, and vacuum hose are all good (I am reluctant to return the booster until the problem is solved). I am rebuilding the calipers but, a second set are on the car and performing consistent with the originals. The pedal is soft with the engine off (i.e., booster off) and even softer with the engine running. NO FLUID LOSS. Steel brake lines are dry and free of kinks. The caliper ďautopsyĒ revealed no anomalies. One thing I have not done is to check wear on Power Slot rotors (< 2 years and 2000 miles) and Hawke HP+ pads (< 1 year of track only). I use HPS for street.
I am slowing down on my performance driving but still do 1-2 track days and a few autocrosses. My Ď02 Z06 is officially a member of the family. Love the car but, this problem has stumped several of us.
Any similar experiences?