[frnugent]

With my 54 reg 1.9 dci megane tourer stationery, I hear I hear a hissing noise from the front passenger footwell and when I press the footbrake the noise is temporarilly supressed. When the car is moving I hear the same noise continually but again it is supressed when I press the brake pedal.
Help would be appreciated. Should I have it looked at urgently? Is the car safe? Is the problem expensive.
Thank you. F R Nugent

 

[Guest]

Hello and welcome to the forum

It sounds very much like you have a leaking brake servo unit. The unit reduces the amount of effort required to be exerted on the brake pedal. So in time if the leak gets worse the amount of effort you have to exert on the brake pedal is likely to get more. The brakes won't fail but it won't be very pleasant to drive.

The servo unit works under a vacuum with diesel engines there is usually a dedicated vacuum pump that sucks the air out of the servo unit and thats the hissing you can hear air being sucked into the servo unit because the rear servo seal is leaking.

I'm not familiar with your car but I know on some cars access to the servo is very difficult and can make for a long costly job on labour.

A 2nd servo will probably cost around £30