2012-2014 BMW 3-Series, 4-Series, X1, X3, Z4 Recalled To Repair Braking System - The Car Connection
The problem with these late-model vehicles is rooted in the brake vacuum pump. The fix for the problem involves installing a locking ring in the camshaft, which will hold the camshaft seal disk in its proper location and ensure the brake pump works as expected. Source: www.thecarconnection.com
