Brake Problem, master cyl??

[Pat]

Took my s3 out today.. Most of the time the brakes are fine BUT every so often the pedal goes nearly down to the floor.. You pump it again and the brakes are back..

I`m thinking master cylinder has failed, could i be right???

 

[S3SYD]

try bleeding the system first...:icon_thumright:

 

[Pat]

I got a replacement cylinder today... BUT the old one has 2 sensors on where the new one from GSF has only one..

 

[golf]

Did you try bleeding the system first? When was the brake fluid last changed?