hi ive got a subaru impreza 97 ive replaced all the brake pads and discs, the front drivers side calliper was ceazed so took apart, cleaned and put back on all seemed fine but when travelling at high speed 90+ then go to brake the brake pedal goes hard and cant slow down until the speed drops off its like the pedal releases itself when it drops speed then i can brake fine . does any oe have a solution to this ?(could it be my abs?)

 

Solution.

Don't drive at 90mph+

LOL.......

 

Have you changed any pipes under the bonnet at the same time as doing the brakes?

 

Sounds like a vacuum problem. As above have you changed the servo pipe and not put the one way valve back in?

 

hi i havent changed any pipes at all.

lol matty.

 

I have the same issue in my 54 plate Hawkeye WRX Waggon with Brembo big discs and calipers. Its not speed related but does appear to be turbo boost related - if I go from boost quickly to brakes, the pedal servo doesnt seem to work - like its pressurised instead of vacuumed.

This was occuring before I replaced the rubber brake vacuum pipes with silicon hose and I didnt see any non-return valve that i may have removed. It also tends to stall on final stopping at a junction with the result of loosing all vacuum - and brakes!!!!

As soon as a quick release and re-apply of the pedal happens, the brembo's stop it on a sixpence - but soon that wont be in time i'm guessing...

Any help appreciated... Cheers.

 

there is a one way valve in the servo pipe you removed. Hopefully you still have the old pipe. Its not easy to see but is pushed down
inside the pipe. Remove it and fit into your
new silicone pipe and all will work again as it should. If it was the same before the pipe was replaced and its definatly not in the old pipe then your gonna need to get one