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Matt, Mechanical Engineer
Category: Audi
Satisfied Customers: 22765
Experience:  BEng hons Mech engineering, in auto industry 22 years
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Hi, my Audi A4 brakes failed me today. The brake pedal was

Customer Question

Hi, my Audi A4 brakes failed me today. The brake pedal was rock hard. I am planning to take it to Audi as it's still in warranty and will not be driving it until it's fixed (apart from the short drive to the garage). My worry is that they will fob me off with "intermittent fault" diagnosis. I gave no intention of driving this car ever again if they cannot find and repair it satisfactorily. It's an Audi A4 Avant 2013. Any advice please from a worried abd petrified mum? Thank you, Tracy
Country: United Kingdom
Make: Audi
Model: A4 Avant
Year: 2013
Engine: 2.0
Submitted: 3 years ago.
Category: Audi
Expert:  Matt replied 3 years ago.

this sounds like the brake servo has either got a leaking vacuum hose or its split inside

on the brake master cylinder there's a servo which uses engine vacuum to pull the brake pedal down for you

if the vacuum is lost then you get a hard pedal

the brakes will still work but will need a big push to work

if its just the hose then this is easily and cheaply repaired

if its the servo itself then this will be more expensive ( part is about £100)