2001 E430 Sport:

I had a problem with the keys, and new ones seemed to help. But in the last two weeks, the car has not started twice, and almost didn't start once. I am thinking it has something to do with the car's security system.

About two weeks ago, after I had driven the car for an hour or so, parked it, came back in about an hour, I stuck the key in, turned it, let go like always, and it cranked for an extra second or two, but started, and set the CEL. I drove it, it ran just fine, and got the usual 25.5 mpg on a four hour highway ride. So I don't think it is an engine issue. I got home, turned it off, and locked it. Next morning started right up , and CEL is off. Ran fine for about a week.

About a week ago, same deal, I had been driving, parked it, came back about an hour later, I put the key in, turned it, let go, and it cranked without starting for about 5 seconds, times out, and stopped cranking. I tried to restart it about a dozen times, all with the same result. Then it started as usual, no CEL, but the died a few seconds later. I opened the gas cap. That did not help. I tried a bunch more times, finally started, set the CEL, and again ran fine at highway speeds and got good gas mileage. Next time I tried to start it, it started right up and the CEL was off again.

Today, it happened again. I drove somewhere, turned the car off, and 15 minutes later, it would not start. It would just crank for about 5 seconds and then stop all by itself. I only tried a couple of times, but had to leave. So, I was with somebody at that point, so we left in his car. I locked the car. But before we drove off, I unlocked and locked the car a few times before we left. Came back, unlocked the car, started up just fine, but it set the CEL again.

Any clues as to what it might be? With the CEL turning off at the next good start, will the code still be set?

__________________
Thank You!
Fred
2009 ML350
2004 SL600
2004 SL500
1996 SL600
2002 SLK32
2005 CLK320 cabrio
2003 ML350
1997 C280 Sport