Brake servo restricted

[ian.f]

Concurring with the above posts. 

I’m astounded at Audi’s behaviour completely through the ownership of my A4. 
It cost me £16,000 in 2019. I’ve had so many issues with it, like this ABS issue, ECU failures, I think I’ve replaced every sensor under the bonnet, AdBlue sensor failure, etc, etc. I’ve spent £9k to date and I’m currently looking at another £1.2k on having to drop the gearbox out to disassemble it to get at, wait for it, another sensor!

Audi have refused to acknowledge any inherent issues with the B9. All they say is “book it in for a diagnostic” then quote me crazy prices to fix things I can do myself or others can do at half the cost.

This was my first Audi, and will be my last VAG vehicle.  

[kh904]

Ouch! You've had particular bad luck with your A4!

Mine hasn't been too bad in terms of non-wear and tear repairs, but then again i don't do many miles (around 3k a year)!

[MarkH13]

2017 RS5, and had the dreaded brake servo and stop/start warning messages this afternoon...

Luckily my car has an extended warranty, so I've called Audi Assist, and someone is on their way - hopefully they'll be able to fit the sensor, and there will be no damage to my ABS! 🙏

[kh904]

I'm sure you will be okay since you've called Audi Assist as soon as you got the message (assuming you haven't done many miles and hard braking since).

[MarkH13]

Thank you, I do hope so 🤞

[P3N]

Good luck Mark.  Let us know so we can enjoy the relief.  I heard that Audi Assist carry this particular part as standard practice now.  Very telling that 🙄

Edited September 30 by P3N

[MarkH13]

Thank you very much - unfortunately it wasn't as simple as I hoped, the diagnostics came back with a bunch of errors (including ABS!) so they're having to take the car to Audi to get it all checked out... A bit frustrating, but at least Audi Assist provides a courtesy car, which I didn't know, so I'll still be mobile 😃

[GreyknightV6]

Had the dreaded warning appear on my S4 last week, so stopped using it and took it to the garage.

They advised me to contact Audi to get it done FOC, but Audi were having none of it.  Garage diagnosed it as the brake booster, what the going cost for the repair?

[ian.f]

1 hour ago, GreyknightV6 said:

Had the dreaded warning appear on my S4 last week, so stopped using it and took it to the garage.

They advised me to contact Audi to get it done FOC, but Audi were having none of it.  Garage diagnosed it as the brake booster, what the going cost for the repair?

Are they sure it’s the booster? Not heard of the booster itself going bad. Have you had the sensor changed? If not, try it yourself. It’s really simple if you can diy a bit. The sensors are about £20ish when I last checked. Am replacing mine again soon…it’s part of my yearly routine!!

[Sid2020]

Il shed my insight on these sensors as I deal with vehicle electronics a lot. The sensor on the servo is more of a safety device that has been used for years and often puts faults in stop/start systems and cruise controls systems, the restricted brake performance is the vehicles ecu reducing the limits of the abs pump/ module. It is worth buying a new sensor from the likes of eBay and fitting yourself. No coding required and system will reset after a certain amount of driving, sensor replacement will not involve any fluid loss so is a DIY job