On occasion my Mercedes Benz C220 will turn over, but not start. After finally getting it started, I took it to a Mercedes Benz dealer. The first time, it took a couple of weeks to get it to duplicate the problem. They replaced a chip in the computer. The next time I took it in they had it for 3 weeks and could never get it to duplicate the problem. After about a month, it is doing it again. The last time it occurred, I turned the car off and got out. I got back in and tried to restart it. It finally started after 5 or 6 attempts. In the past it has taken as long as 20 minutes of constantly trying to start it before it finally started. I really like the car otherwise, but I'm currently looking to replace it.