2011 BWM 335d with many 4D35 fault codes

Recently bought a new 2011 335d and during the past 4 months of driving, I have the "Service Engine Soon" check engine light come on three times already with less than a total of 5000 miles on the engine. The first check engine light came up at only 2000 miles!

Each time the dealer says it is a #4D35 fault code from the Reducing-agent metering valve. The first time they cleaned it out to clear the code. The second time they replaced the valve, but the code still came back 6 weeks later. The third time (this weekend), the dealer cleaned the valve again. What is going on??? Seems like the 335D is a lemon with some major design issues with the diesel system. Anyone else have this problem? I'm starting to regret getting the 335d.