Ok- I was going to make fun of 335dM for making stupid modifications. But he may well be onto something valid. After some poking around, it seems like the 335d is the only diesel in the US market without a diesel water separator. Is BMW relying upon a hydrosorb filter element or is BMW just pumping the water through the injection system because they want to make the US cars "maintenance free" at the risk of expensive repairs?
And before one is tempted to reply "this is not a problem because there is no water in the US diesel supply" one should note that every other diesel I have actually captures water in a separator and requires draining somewhat often.
So why does every diesel manufacturer in the US market but BMW supply a water separator? Does BMW utilize a water-absorbing filtration element to protect the injection system or should owners be following the lead of 335dM and looking for an aftermarket system?