I read a previous post about the crank position sensor, and makes me wonder what is up with mine now. About 2 weeks ago, wife called and had started the ML, drove about 3 blocks, went in to buy some groceries, and when she went to leave, it would only turn over, and not fire/start. She tried 5-6 times, and nothing. I came down after it sat for about 15 minutes, put in my key and away it went. Ran great since. Now today, I started it, drove it around the block to my front driveway, shut it off and about 20 minutes later, it was dead, same as before. Tried several times, let it sit for 15 minutes, and away it started. I left it idle and after about 5-8 minutes, it just stopped and nothing again for 3-4 tries, let it sit 15 minutes, and away it went. Drove it around the back to my shop and Mercedes mechanic was giving suggestions over the phone. I am the second owner, all records up to date when I got it last August, and he (original dealership) figured the plugs were due, since it has 90,000km (55,000 miles), I pulled the (I think original Bosch) plugs, and the platinum tip was totally gone on all of them! Changed them out with NGK and starts fine 10 times, drove it around some. Could this be MY issue, or is the CPS still suspect to all this?