On Saturday, I purchased a 2005 C230 with 27550 miles that had never been wrecked. I drove it over the weekend and for a few days thereafter with no problems. On Thursday morning, I drove it 4 miles to work and parked it until noon at which point in time, I drove it about 6 miles to get some lunch.

On my way back to work after lunch, it started acting VERY strange while stopped (in gear) at a stop light. The whole car started shaking for a few seconds and then it would stop shaking for a little while. Then it would shake again for a few seconds, then stop. It did this about six times while I was stopped. I remember that the car was shaking so bad that she shift knob was vibrating. It looked like the RPM's were going up a little bit each time the car started shaking, too.

Any clue what this would be? I did a little research on the vehicle before purchasing and know that some of these engines have valve trouble which is remedies by replacing the compressor head. What are the indicators of such a problem?

The good news is that it is still under factory warranty. It is at the shop now, but the tech hasn't been able to replicate the issue. Not sure what set it off or what could be wrong with it. If you have an idea on what the cause could be or what made it happen, please let me know.

Many thanks,
Anita