Yesterday I had my codes pulled and 3 came up, (P0301, P0300, P0400). I replaced the plugs and reattached a vacume line that was off, from the EGR valve. I reset the computer and then last night the engine light came on again. When I pulled the codes again the P0400 code came up again. (EGR flow malfunction)
I was reading another post where the tube to the EGR valve was clogged. Is this something that is common on all models, or is it just that time for my year of mercedes to replace the EGR valve?
I was hoping that the vacume line that was disconected would solve my problem, but it only took about 5 miles of driving before the engine light came back on.