WHat does lots of black smoke mean?
 

Thinking of getting a 300Sd the owner states there s lots of black smoke out of the tail pipe when accelerating. The car has been sitting for 2 years. Thanks

I would think it's unburned fuel except that it has been sitting for so long. Maybe it just needs a good Italian tuneup or some diesel purge.

Unburnt fuel. Clogged air filter, valve adjustment past due, bad injector(s), stuck turbo, low compression, etc. Anything that will cause the engine to be starved of enough air to complete combustion.

one more thing
 

He also stated the car lacks power. Black smoke plus no power= bad turbo maybe??

It could be a bad turbo. It could also be a very plugged up air filter. Valves out of adjustment could do that also, but I think would probably cause hard starting if they were really tight. Really loose might smoke a lot but with easy starts, however these engines tend to get tight on the valve clearance when they aren't adjusted regularly. Late timing might cause similar symptoms.

It means that nobody will follow you!:D:rolleyes:

no mosquitos in your neighborhood either.

It means an overly rich fuel condition! :eek: This could be a lot of things and good posts above explain some of these. This needs further investigation.;) How many miles on this vehicle?:confused:

It should be fixed asap. Black smoke results in very high exhaust temperatures which can easily damage the engine.

I assume the car is in N. VA as well. Mild winters warm summers. Check fuel lines for microbe build-up.
Everything else recommended Forced should be looked into.

Zill.

It could be something as simple as a broken ALDA line or some other boost leak.

Thanks
 

The car has around 300K on i. I will check it out and report.

Broken ALDA line would result in less smoke because they would be no extra fuel with the boost.

look at the alda and see if the cap is disturbed, it could be as simple as a kid was playing with it, and cranked it all the way over.
my bet is on the air filter though.

Forced,

Wrong again. Its lean mixtures that cause high exhaust gas temperatures (EGT).

Gasoline piston engine airplanes have carburators that have manually adjustable fuel mixtures. The mixture is leaned out for maximum power an economy. BUT the pilot watches the EGT gage so as not to not make the mixture too lean that will make the EGT too high and damage the engine.

Small 2-cycle engines (chain saws, weed whackers etc) can be tuned for maximum engine speed by leaning the mixture but if its too lean, the engine will run too hot and may sieze (don't ask me how I know this). The proper way to adjust the fuel mixture on these engines is to use a tachometer and only adjust the fuel mixture for the maximum engine speed specified by the manufacturer.


I know it seems logical that the more fuel, the higher the EGT. But that's not the way it works on the real world.

P E H