Hi guys,

The new to us Volvo V70XC has an air leak when your foot is lifted off the brake pedal. It happens about 50% of the time. I will brake and then after i let my foot off i will get a hissing sound for a little while. I did some searching and found some posts but they all seem to indicate a hissing sound when they apply the brakes not when they release them. The leak also affects the cars idle when coming to a stop, it lurches forward a little right before stop when the rpm's are at there lowest when its in gear.

Is my problem the brake booster or just a leaky hose?

Thanks,

 

Check your vacuum connections for the brake booster. You may find one loose. Have someone press/release the pedal while you're looking/listening.