2007 CLK550 with 60k miles. Runs great. Never an issue.

Drove car for about 1 hour. It is hot here (90+). Parked it and it sat for about 3 hours in the early evening. Came out around 10:00 and no start. It cranked but no start. Went inside and did some reading online and it seemed like it could be the CPS. Engine was still warm. Took a hose and ran cool water down the drivers side firewall area (location of CPS) for a few minutes. Got back in and on 3rd or 4th try it came to life. Drove it home 1 hour and all was well.

Next morning I took wife's car to MB dealer and got a genuine MB crankshaft sensor (needed my car) and went home. Installed sensor and it fired right up.

Later that day I took car out for another drive of about 1 hour. All ran well. Parked it for about 2 hours and it re-fired right up. Drove home about 1 hour and parked it for about 3 hours. Came out to take a nice drive out for dinner and back to a no start (cranks but does not start).

Had dinner (about an hour) and came home and it fired right up.

Tons of reading tonight and everything suggests the sensor. There are no codes. When it starts it runs like a dream.

Could sensor #2 also be bad? Something else?