When the air temp is cold (<35-40 degrees) the car starts fine. If it gets above 45-50 degrees and the car sits for more than 15 minutes after being run and brought up to operating temp, the car won't start on the first 3-4 tries unless you depress the gas pedal. Then when it does fire up, it runs rough for 1 minute then smooths out. Other than this one problem the car runs great The MB dealer just did the 60k service 2 months ago (plugs, filters, fluid changes, etc.) and has replaced the following parts since; fuel pump, coolant temp sensor, gas cap, & a vacumn line. They can't find anything in the MB TSB's about this problem and suggested that we start replacing components, beginning with the fuel injectors, in hope of finding the problem. It's Christmas and all that, but I don't want to fund an expedition to rebuild what seems to be a perfectly good C220 other than the one hard starting problem. Has anyone else had a similar problem and if so what was the cure?