Hello,
Can you suggest what could be the problem with my car(270 cdi, w211).
Sometimes, on startup engine(not so cold start) for a few seconds(5-10) there is white smoke from behind the car and engine is not working stable. Looks like one or more cylinders not working. Also there is a strong vibration from engine.
This happen not every time, but regularly. I checked antifreeze level, it's constant. Engine oil is also constant.
What could be?

 

Injector poss leaking into cylinder slightly, burning oil or head gasket problem, what does the smoke smell like

 

I'm not sure, next time i will go out of the car and check it.
If there is a problem in injector, how this could bring problem to head gasket or engine oil? How serious is this problem?

 

Plutoe, thanks again for quick response! I appreciate it. You can see, by my situation and questions, that i'm not so familar with engines, so maybe i need more detailed explanation.


I'm happy when there are people who spend their time to help others.

About my problem, as i said .. the problem is repeated, but not every time. After engine start, after 5 to 10 sec. everything is ok. If i push the throttle in this period of time when engine is vibratihg, white smoke appears from behind. Engine is clear, on the top of it.
You said injector(s)... Try to clean them with "bardahl"?

 

Thanks again!
I don't have CEL. I think you are right, that i need a good diesel engine service. I just hoping, that i have more time until go to service, i mean it's not emergency.

 

Sounds similar to a glow plug not warming that particular cylinder on initial startup, white smoke in a diesel is usually unburned fuel. Use a laser thermo gun to check exhaust manifold temperature when first starting, replace faulty glow plug or plugs.
Engine probably runs smooth when warm, correct.
Good Luck

 

You are right, this happens right after engine starts and continues 5,10 seconds. After this everything is OK. It's important that this never happen on cold start. I see it only when engine is still warm.

I checked engine oil, coolant .. level is ok.
I replaced broken plugs months before. There isn't error when check with DAS for glow plugs.

 

1 Injector issue
If this condition (white smoke) is on a warm engine and smells of diesel then you have an injector leaking into the cyl when shut off and when restarted the excess diesel is not burned at first because of the rich condition but soon fires 5-10 seconds after start.
This also could explain the rough idle on cold start.
2 Glow plugs are easy to check, remove the power wire going to each glow plug and check for continuity (resistance) from the power terminal of the glow plug to the engine block, you may still have a glow plug issue.
As others have stated smell the white smoke when this happens, sweet smell is antifreeze which will form a white cloud out back and does not dissipate quickly, diesel smell is unburned atomized diesel fuel and should clear fairly quickly behind car.
What is the mileage?
Any leakage around the injectors?

 

Critter, thanks for rich explanation.
I think, it's smells on diesel.. also it's dissipate quickly. On cold start(morning now in Bulgaria is around 0 ° C, 32 degrees Fahrenheit) i don't have this problem. My car has 200k km(~130k miles)

 

Problem solved!
After test of injectors, 4 from 5 injectors with abnormal values for idle work.
I recondition all 5 injectors($150 per injector) and everything is ok now.