Hello CLK320MIA,

I'm having the samre problem with my w202. Tried replacing the switchover valve block and manifold under the hood with no positive results. I would like to do the same thing you did. Just wondering, where did you get the check valve ? Is it oem ? If it is, can you please give me the parts number ? I know it sounds stupid but I'm living in Italy and unless I tell them the exact part number, the answer I will get is they don't have it. If it's not oem, can I order that from fastlane ? Thanks in advance.

Willy