Neil forget the "noise"
You will need to replace the TBA (Throttle Body Actuator) $540.00 here at MS and $950 ish at MB dealer.
In plain english - there is a potentiometer encased in a circular black housing (circumference of half dollar) on the right side of the Throttle Body. That pot will deteriorate due to heat of engine affecting it. Mine went with only 31K on the clock. Engineer told me it is not a mileage related thing, it is a heat related thing. Mine started intermittant in March 01 to full time by July 01. The engineer said the pot started dying in March and just $hit the bed in July. You have to be a licensed MB part rebuilder to acquire just the potentiometer (cheap sub assembly). The MB engineers that designed the rig realized it was a crap idea because there was no way to heat shield the pot. The 1995 model ASR is totally different( PC card controlled-no pot) and mounted (on the firewall, I think) away from the heat of the engine.
Live with it until it goes full time.
A less expensive solution than my route with the dealership:
Buy the unit here on MS. There are only 4 bolts and a gasket to swap out. When you are finished installing it, "limp" the car to a dealer with full diagnostic computer or independent with an HHT and ask to have the codes cleared. Although it only takes a few minutes to clear codes, you will prolly still be charged for 1 hour work.
(An authorized MB dealer charged me $900 something for the TBA plus 5.5 hours labor totalling $1500 something.)
It takes about 2 minutes to unfasten the air cleaners and ten minutes to unbolt existing TBA. 15 minutes to clean/prep surface for new gasket and 10 minutes to rebolt new TBA, plug in the pot to the harness and remount aircleaners.