Yup, sounds like your OVP is the culprit... do a search and you'll find all the info you could ever need on it.
Where is the throttle body... is it where the accelerator opens "whatever" to let any given amt (accelerator position) into the engine? I ask this because sometimes when I am going very slow and turn the wheel all the way, putting resistance to the wheels, the car almost feels like it is going to stall, never has, but this happens all of the time. Thanks.
2006 E350 w/ 155k miles (Daily Driver)
1993 300E 3.2L Sedan w/ close to about 300k miles
2003 E500 Brilliant Silver (Had 217k miles when totalled!)
1989 300E with 289,000 miles (had for <1 yr while in HI)
03 CLK 500 cabrio (Mom's)
2006 C230k (Dad's)
1999 S420 (Mom's/Dad's)
2000 C230k Sport sedans
2001 CLK320 Cabrio (Mom's)
1995 C280 My First Mercedes-Benz... (155k miles. EXCEPTIONAL AUTOMOBILE. Was Very hard to let go of!)