What I know: From the rectangular diagnostic connector in front of the battery using the built in LED/SW at PIN #2, I retreived the following codes.
http://www.troublecodes.net/MB/
6 - Idle speed control inoperative.
22 - Cam position sensor signal defective.
25 - Knock sensors.
Sounds like #6 could be a $1000 throttle actuator... "Regarding code number 6, your idle speed is controlled by the throttle actuator, which is a very expensive part - about $1,000. "
Any chance that the #6 code could be caused by the Cam Sensor, or the Knock sensor(s) failing?