One problem related to gas recirculation valve (egr valve) has been reported for the 2008 BMW 3 Series. The most recently reported issues are listed below.
While the car was travelling at a rate of about 45 mph, it did something I never experienced before. It started to shake, sputter and lose power while ascending a on a paved city street that had about a 20 degree uphill grade. The vehicle behind me didn't expect my sudden speed change and nearly rear ended me. . The engine icon appeared on the dash and I sputtered all the way home.