That is the valve that seats under the boosters and that distribute the pressure between the two boosters.

Is that really the function of this part? Or is it simply to detect when one of the circuits has less pressure than the other? If I am correct, you car will stop just as well without this valve - you will just detect the loss of one circuit by the fact that the car takes twice the distance to stop (OK, it isn't that simple) rather than by a light illuminated on the dash.

 

Alfa Jay..you are probably right, but i would like to keep this car as original as possible and try to solve this problem that has been facing other owners..

 

Check with Papajam.....he just might have one available.