I am having random misfire and total cutout problems with my 1999 500Sl.
The misfires usually occur if the car has been sitting for more than a day but clears if it is restarted a couple of times.

The new added ,very serious, problem is the engine will shut down while in motion and in traffic. In a few cases I was able to restart the engine and proceed but in the last case it had to be towed but it did restart after it was unloaded 2 hours later.
When the engine shuts down the check engine light does not come on and there is no code to read.

Any help would be appreciated.

Thanks

 

Using my Actron code reader I was able to locate the misfires. Replacement of the spark plugs eliminated the misfires.
The engine cutout problem was more difficult however. Referencing jmccartney81's 11/10/2008 solution of replacing the crankshaft positioning sensor was the answer. Replacement of the CPS eliminated the engine cutout problem.