The wonders of modern technology,if there's no error code no one knows what to do! back in the day they'd have have adjusted your fuel mixture lubed your throttle cable and sent you on your way a happy man. Oh how times have changed!
Sorry I can't be more help, although I'm sure there are people on this forum who can. It may be helpful if you could state the model of c-max you have and whether it's petrol or diesel.
2007, 1.6TDCi Ghia Tonic Blue