One problem related to timing tensioner has been reported for the 2012 BMW 328. The most recently reported issues are listed below.
BMW refused to recalls 2012 to 2014 vehicles with faulty timing chains, oil chain, and tensioner. When I contacted BMW they stated it was only covered to 70,000 miles. I purchased a 120,000 miles warranty , I was never informed by BMW west the service center about this recall. At a 120,000 miles took my car into be serviced and was told the timing chain, oil chain and tensioner needed to be replaced at the cost of 4,400. 00, if the the chain had came off of the tensioner and ruin it motor that could be from 12,000. 00 to 22,000. 00. So many are experiencing the same problem. My car has been sitting for 6 months unable to drive it due to the danger . Car makes I high pitch whining sound and jumps out of gear, check engine light states on.