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Fred Thornton
27-04-2009, 02:29 PM
Hello,

I drive an A6 2.0 with multitronic gearbox registered in Jan 2004.

On several occasions over the last year I have noticed (intermittently) what can only be described as a complete absence of power assistance during braking.

I mentioned it during the last service but they found nothing untoward, which is unsurprising as it happens randomly.

Has anyone else noticed such a problem and if so what can I do?

Thanks in advance,

Fred.

Crasher
27-04-2009, 03:44 PM
Petrol or diesel? Sorry, stupid question of course it is a petrol, the 2.0 TDI didn’t come out until 2005. Has it had water getting inside the car?

Fred Thornton
27-04-2009, 03:48 PM
Petrol - MW2 Audi option code (4cyl, 20V, 96kW) if it helps?

Crasher
27-04-2009, 04:57 PM
There is a possibility of servo damage from standing water in the plenum chamber and also the electric vacuum booster pumps are prone to failure.

Fred Thornton
28-04-2009, 11:35 AM
Thanks Crasher, are these expensive to check?

Crasher
28-04-2009, 01:01 PM
It takes about an hour plus rebleeding the brakes after if there is nothing wrong. The vac pump can be tested with a diagnostic system in output tests.

Fred Thornton
28-04-2009, 03:50 PM
Thanks, I'll let you know how I get on.

Fred Thornton
06-06-2009, 08:18 PM
about 3 weeks ago the car stopped driving and according to the local main dealer I need a replacement valve body for my CVT gearbox.

Apparently this brake problem can also be caused by the gearbox! IS THIS TRUE?

Crasher
06-06-2009, 08:31 PM
Never heard of that one and can't think how it would affect the brakes but these CAN BUS systems can do odd things.