What is the proper idle speed in a '99 SLK230
w/ 5 speed. Mine hovers around the midpoint between 500 and 1000rpm, while sitting at a traffic light. Sometimes,not all the time, it idles rough and I can see the needle jumping very slightly and the car shakes a little with it. My question: Is this normal??
Would like to find input from other SLK owners. Mileage is 2100 miles.