Yesterday I had the oil changed in my '97 C-230 and on the way home the CEL came on. The code was: P0400 Exhaust Gas Recirculation Flow Malfunction. I turned it off and today the light came on again with the code: P0410 Secondary Air Injection System Malfunction. My guess is that they disconnected a hose or something but I didn't see anything after a quick check under the hood. Any ideas on this? Thanks
-Dick