my partner has a pug 206 1.4 and whn the brake pedal is pressed air is hissing from the servo into the air intake pipe does any one know wht causes this. is it the servo unit.
This is fairly common. If the brakes are still OK then you can just put up with the noise, but if the brakes begin to be affected or the noise is too off-putting then a new servo should cure it.
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