I took my Benz out for a spin the other day and I noticed that when I floored the gas pedal, while accelarating really hard there was black smoke coming out of the tail pipe. Is this a normal symptom under heavy acceleration? Probably not since I had never noticed it before. The car is in overall good condition, runs smoothly at all speeds, gets decent mileage. On the downside it started to consume some more oil than before (but burning oil or even coolant would cause blue-white smoke, wouldn't it?).
I'm a bit concerned because this is the first time I saw black smoke out of this car and I hope it doesn't mean big $$$
While searching the forum I found something called "italian tune-up". Is this only for diesel cars? Or maybe I should add some injector cleaner?

__________________
1987 300E 185k miles

Full power = full fuel. Black smoke = unburned fuel. While it should not leave a cloud like a diesel, it is not uncommon to see black smoke from high-performance gasoline engines under heavy acceleration. Your fuel economy could be low if the injection system is biased towards too rich all the time, and a lot of unburned fuel means the catalytic converter(s) have some overtime work to do. You might have your fuel management system checked.

You certainly can try the 'Italian' method of tuning, it won't hurt the engine. You could also have the fuel management system checked...

Best Regards,
Jim

OK. Thanks. I asked my brother to drive my car while I drove his right behind. It's in fact rather a black puff than a big cloud of smoke when the gas pedal is floored at around 60- 70mph and another puff when the pedal is released. There is actually much more black smoke while accelarating at full throttle from 0 mph.

I get aroung 20 mpg driving mostly in the city which I assume is quite OK. 24 mpg on the highways.

__________________
1987 300E 185k miles

Might first of all be worth replacing the air filter as any restriction will cause an increase in fuel consumption and could be the reason for the black smoke.