What is the urea concentration?
Originally Posted by bimmerdiesel
4D35: metering valve is clogged/partial clog due to crystalized DEF. Dealer should check the valve to see if its work. They will flush it with warm water, if doesnt work then they would do warranty replacement of the SCR Metering Valve. Part # 18-30-7-807-206.
Copying this info from another 335d owner met him on dealer service bay who also had same issue and his work order said this info
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