I have a problem.
Brakes difficult and the pedal vibrates by pressure.
Pump pressure in norm. But on a cold motor, steering weel is not pivoted.
When the engine will get warm, steering weel all over again can be turned to the left, and then after a while to the right.
I have replaced a bomb, but it not new. As it correctly to test.

Hi Dmitry,
Nobody has replied to you yet so I feel challenged. Take your Audi to a good mechanic. You don't give us too much information about the car and it's behaviour so I can only assume that it is a V8 with a really rough braking system. The brakes in the Audi V8 are probably the most complicated
part of the beast (front ones) along with the transmission and the cooling system, second to one Porsche model according to my mechanic. Please tell us if the ABS system bothers you in the long St. Petersburg winters! That's rough!
All the best,
Florin

Hi, Florin.
Thank for the answer. I work technical director of car-care center of BMW in
Nizhni Novgorod. Our firm the official dealer of BMW.
I have the supreme automobile education. In service 11 years.
I have Audi v8. The machine very much is pleasant to me. With brakes this problem began recently.
I thought, that it is a bomb. I have replaced it. For some time the problem has disappeared. Then has appeared again.
I have replaced a forward part of the pump with pistons. All began to work normally. Now again the same problem.
By sharp pressing a pedal of a brake the pedal stops above and brakes are not present. ÀÂS works normally.
The pedal does not vibrate as at work ÀÂS, and under a foot the pulsation of a liquid is felt, and the same pulsation is transferred in
Steering wheel.
Now a problem in the information. I can not find the circuit and a principle of work of the hydraulic booster of brakes.
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