The BMW 335d and X5d were close to not passing the CARB.
These diesel cars needed special approval in order to be legally sold in the state of California. Both cars have been conditionally certified because of the rough standards on emissions. BMW is allowed to start selling their vehicles, but with each sale a fine will be emitted by the CARB. In total, there were 7 problems which have been discovered and which need to be solved by the people from BMW. If the problems don’t get fixed, the company will have to pay more for each car they sale in California, or even worse, they can lose their conditionally certification.
At the moment, the problems are unknown and everyone is waiting for a solution from BMW.