Several weeks ago we found a beautiful, garage kept 2002 CLK-430 with 65,000 miles on it. We have all the service records and it appears that all maintenance including A and B services were done in a timely fashion.

When we first got the car I messed with the S-W while driving (thinking it was similar to something we once had in a Volvo) forgetting that the book said you should only do that while stopped and in "Park." Pulling out from the first traffic light it seemed that the accelerator was hardly influencing the engine. The car barely moved ahead and just did not want to go and did not want shift. After getting out of traffic, stopping, shutting everything off, and waiting a few minutes, I restarted the car and it worked fine.

Yesterday, weeks later, my wife called me from the grocery store parking lot to tell me the car was doing the same thing and would hardly move. I went and got the car and it worked fine. All shifting was fine and appropriate. Acceleration was as it should have been. The check engine light was not on. At one point on the four mile drive back home, I floored the accelerator from maybe 35 mph to perhaps 60. It accelerated appropriately, but the check engine light came on.

The car continued to shift, and act properly but the CEL did not go out even after the car had been shut off for a few minutes and then restarted. Today the light is out and everything seems to be fine. I have been unable to duplicate the shifting problem that my wife experienced yesterday.

Three questions: #1. What could have been the cause of the shifting problem (my wife asked me if I had been messing with the S-W switch again- which I had not)?

#2 Any idea why the CEL came on, and why it is now off?

#3 Did the light have to do with the shifting problem or the hard acceleration?

I have ordered an Autel MaxiScan MS300 Can from Amazon which I should have by Tuesday. Since the CEL has gone off will there be any codes to read?

Any help, thoughts, or suggestions would be greatly appreciated.