Hi all,

So, I have been watching this carefully, and am wondering whether I ought to be concerned. Here's what I observe:

I have a 1984 300D Turbo (123.123 with 617.952 motor). When the engine is warmed up and at operating temperature (coolant anywhere from 80-90 degrees C) I can drive around town in "S" and get a very tiny puff of smoke on starting from a full stop, and can also occasionally see a larger puff of smoke when I hit about 2500 rpm in 3rd gear, if I am accelerating moderately hard. I most recently observed this on an extensive (about an hour) drive around town and the behaviour was very predictable. Once I see the initial puff of smoke, it stops quickly (that is, I don't trail a plume of constant smoke or anything like that)

With the motor cold, or warmed up, I can rev the motor in neutral and I eventually will get black smoke, but not until I hit about 4500 rpm or more. I never see smoke with the motor idling. Blowby on my motor is very minimal - hardly enough to even move my oil cap if I loosen it. Overall, the car feels smooth and really strong, so I suspect I shouldn't be concerned. It might be worth noting that I haven't replace the air filter and do not know when it was last done. Maybe this is a likely culprit?

Also, I was driving around on the freeway in 3rd, pushing the motor up to about 3500-4000 (and driving in that range constantly) and couldn't tell if there was smoke (no streetlamps or following cars tonight) but I did notice after a few minutes that I could detect a distinct "exhaust" smell. Not sure what to make of that.

Lastly, I had some time ago asked about realistic fuel economy, and I am getting about 22mpg in town, after just having filled up and noted my distance travelled and fuel consumed. Not bad for lots of very short drives in cold weather.

Fiiiiiinally, I got my 250,000km badge from Mercedes-Benz, and boy! It looks lovely on my grille! Yay!

Thanks for any advice/reassurance!