Peugeot Forums banner

Peugeot 406 braking problem - failure of brake pedal

2K views 4 replies 5 participants last post by  reliable406 
#1 ·
Can only get a brake when you pump the pedal. Hold the pedal hard and it will gradually go to the floor. Work done so far: new discs on the front, and handbrake linings renewed, which is not to do with this problem as it is a separate system. We have replaced with a new master cylinder and a second hand servo from another car, all brake pipes and wheel cylinders have been checked for leaks, but this still hasn't cured this problem. Anyone else got an answer to this problem.
 
#3 ·
Did you bleed the master cylinder before installation?
I fitted a new MC to our 807 only to have rather long travel & spongy brakes thereafter no matter how many times I bled the system. I only realised this was likely be the cause recently, if there are flexible pipes to the MC you could loosen it so you can get it level then get assistant to pump the brake pedal gently and watch for air bubbles rising in the reservoir. Best.
 
#4 ·
It's nothing to do with vacuum or the servo,as a fault with these would produce the opposite of your problem.A very hard pedal.
If your confident the master cylinder was new and the correct one,all the flexible pipes are in good order and there are no fluid leaks,it's got to be air in the system.
 
#5 · (Edited by Moderator)
It may well be air in the ABS unit as they can get an airlock due to being high up the fluid travels from the master down then up into ABS unit then down again and airlocks are common.

As above the servo/vac side is nothing to do with it the only thing that will do this is air in the system or a leak even a bad flexy hose wont cause that much of a difference.

Its best to use planet/diagbox and bleed following the system on there as this runs the ABS pump and valves purging out the air.

HERMANO start your own thread as your fault is TOTALLY DIFFERENT to the OP !!!
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top