Audi A4 8K Bj.2008 CAGA - Motorentlüftung | Posts 16+

Thank you, Rainer. I didn't know that.

I just saw the same car at the company; it's a bit newer and has the white MFA (multifunction display), but it also has the same issue in the ventilation hose. However, it's not as bad on that one because it's before the turbo. It's also from 2008 with 150,000 km, and has the same parts and software number.

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Not even someone accidentally put windshield washer fluid into the oil filler cap while refueling...apparently, such mistakes can happen.

dieselschrauber wrote:

Quote: Not even once did someone accidentally put windshield washer fluid into the oil filler cap while refueling...apparently, such mix-ups can happen.

We received a call from an elderly woman who had actually put about 5 liters of windshield washer fluid into her brand new Opel, and she was asking why the reservoir wasn't full, and why nothing was coming out from underneath, and why the windshield washer system wasn't dispensing any water, and why the display said: "Refill windshield washer fluid."

The engine survived.
"You won't believe this! Maybe someone actually put water into your engine instead of oil?"

No, no water was poured into it.

If you say so.

Change the engine oil and filter. Based on my understanding of how much water can condense and then evaporate from the air in your car, this amount of water shouldn't be able to accumulate like that. There must be a problem or you're driving extremely short distances repeatedly, which you said isn't the case. Is the coolant level really staying constant?

"That's my girlfriend's car, and I'm the only one who drives it, so I can rule out water getting into the oil. I've been checking the coolant level every two days, and it hasn't changed yet. The car is driven about 100 km per day (all on country roads, with a speed limit of 70 km/h in some sections and passing through 9 villages)."

It's an old topic, I realize that.
However, I would like to ask if a cause has been identified.
I observed something similar during the winter months in the crankcase or in the hose leading to the compressor side of my BPW injection pump (2-liter).
I'm now only using the film for short distances, and I'm noticing that the emulsion is starting to become oily.
It is gray in color and can be removed with a screwdriver.
The oil and water levels are also fine in my system.

I installed a catch tank and I'm observing it. I'll probably see the results in the winter.

I don't see this behavior in the summer, though.

Best regards, Kai.

I've directed the venting into a closed container and empty it during each service. But your problem only occurs on short trips.

I suspected it.
Nowadays, I occasionally take a slight detour on the highway when driving home, just to generate a little more heat in the engine oil.
I installed a 2-liter catch tank because I only want to empty it once a year. It has a vent pipe for inspection.
I will check it for the first time at the end of May, although I think that the warm temperatures are unlikely to generate much water in the oil.
If the catch tank is working correctly, the compressor side should remain free of oil, and the compressor impeller should be free from carbon deposits.
I will provide an update so that the thread doesn't remain unanswered.

It is pointless and potentially harmful to the inlet valve stems to try to make the compressor side oil-free.
2. The compressor wheel is never covered with oil sludge. Never, ever, and not even if pigs fly to Mars. This is ensured by the 100,000 revolutions per minute that the charger makes and the large amount of cool intake air that flows through the compressor wheel.

To be honest, I don't understand the point of your post.

Well, I don't know what that black stuff on the compressor blades is. All I can think of is a thin layer of soot or carbon buildup. I didn't paint it on.
What exactly don't you understand?

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What exactly don't you understand?

I wonder about that in your case. Because the compressor wheel is usually never hot enough for oil carbon to form in significant amounts. If you're referring to a brown/black film, that's normal and doesn't require any action.

In the picture, you can see an old loader that was often subjected to high thermal loads in the past. Everything is within acceptable limits:

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Again, what's your problem?

Best regards, Rainer.

I'm not comfortable with this type of communication in a forum.
If the black layer isn't a problem, then my question is answered.
Thank you!

If you are concerned that the charger might overheat (which can indeed cause oil carbon buildup, but specifically at the shaft bearing), monitor the exhaust temperature.

It should be available in the measurement data blocks of the engine control unit (ECU) for the BPW system and should not exceed approximately 840°C at the turbine inlet.

Best regards, Rainer.