Peugeot 206 w reg 1.4 petrol - hissing when brake pedal pushed

[darbo1103]

When I push the brake pedal, I get a hissing noise from the passenger footwell. I have looked and there is a rubber / plastic washer, which when I look in the engine bay seems to go to the servo(?). Is this hissing a problem (a part from being very annoying)? If I tap the brake pedal slightly, the hissing goes off (eventually). I also seems to get louder when I change gear.

[david1702198]

sounds as though you have an air leak from the brake servo.

[david1702198]

the reason it gets louder as you accelerate is because the vaccum pressure increases as the speed increases so you have adequete servo assistance in order to stop the car at the higher speed

[darbo1103]

Is it a problem then or just an annoyance because of the hissing?

[grinnreaper]

it could become a problem if it was left alone, i had the same thing happen to me with an escort i used to own, i didnt want to fix it as i didnt have the time, after a short while the hissing got louder and the brakes became weaker, resulting in a little accident

[furrycheeky]

I would never leave any fault in the braking system to chance, you don't want them failing, best get the car to a mechanic.,

[david1702198]

it will probably fail an mot anyway as the servo action is checked during the mot, what happens is the car is switched off the brake pedal pumped until hard the car started then they make sure that the pedal sinks slightly to indicate servo assistance, should there be a problem with this it will fail.