I have had two 300D s and both of them idle rough. The first one got smashed up before I could try to figure it out. I was wondering if this is the nature of the beast as a friend of mine has an 84 300td and an 85 300td and they both idle rough too. Once you step on the pedal on any of these cars they smooth right out. You can actually feel the car "surging" when you are at a stoplight in gear with the brakes on. Any thoughts?