Audi S4 owners have reported 1 problem related to power assist brake vacuum hoses, lines/piping, and fittings (under the service brakes category). The most recently reported issues are listed below.
The brakes boost/vacuum assist line check valve cracks apart into two pieces. This causes the total loss of the power assisted brake system in the car and subsequently makes it very hard to stop the vehicle. There is no warning about the pending loss of brakes. One second you have brakes the next it feels like you are trying to push a brick thru the floor of the vehicle trying to get it to stop.
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all problems of the 2002 Audi S4
🔎.