Oil leak in top of engine

[edwinvanhove]

Hello everyone,

I am new to this forum. In The Netherlands i did not find a very active forum to talk about the RS6 C6. I hope someone can help/advice me. I have a 2008 RS6, engine is original (only stage 1 tuned) and is good serviced.

I saw some oil laying on top of the engine. My first thought was that the 4 o-rings where dead. We renewed them (it was indeed about time) but after driving for a week, i found out there is again some oil on top of the engine, under the hoses (see picture 1, under the circle). i don't think it is coming from the new o-rings (see picture 2 where the new ones are installed).


anyone a suggestion? it will probably come to taking of the intake again...

thank you in advance!

best regards,
Edwin

[IanH755]

It could be a possible leak from the Oil Filter housing at the rear of the engine just behind the oil you found but there is also a small oil valve right where the circle is which could also be the issue. That valve is item 33 right at the top of this diagram, it's a Lamborghini part but quite cheap - 079117409F -

https://audi.7zap.com/en/rdw/audi+rs6+r ... 103000/#33

[Stiggles]

Hello everyone,

I am new to this forum. In The Netherlands i did not find a very active forum to talk about the RS6 C6. I hope someone can help/advice me. I have a 2008 RS6, engine is original (only stage 1 tuned) and is good serviced.

I saw some oil laying on top of the engine. My first thought was that the 4 o-rings where dead. We renewed them (it was indeed about time) but after driving for a week, i found out there is again some oil on top of the engine, under the hoses (see picture 1, under the circle). i don't think it is coming from the new o-rings (see picture 2 where the new ones are installed).


anyone a suggestion? it will probably come to taking of the intake again...

thank you in advance!

best regards,
Edwin

As Ian says could be either the oil filter housing or the oil cooler leaking oil

I had the same issue after the local Audi dealers broke the housing when re fitting the engine after doing the oil pump seal. Unit 20 sorted both right out for me thankfully.

[edwinvanhove]

Thanks so far, probably will take off intake again for a good check.

@Ian: I don't think it is part 33, because that part is in the front of the engine, and as far as i can see there is only oil under the circle i drawed, if part 33 is leaking i should have seen more oil in the front and middle on top of the engine i think.

[cammmy]

I can't advise with your issue but if you take the inlet off again, I would advise going a little further and get the injectors out for a service. There's a plastic filter in them that can disintegrate and destroy they engine. Mine also had a pretty poor spray pattern and a couple were leaking, even though it's been run on premium fuel it's whole life. I can recommend a place in the UK if you can't find anyone locally. Just be careful as the plastic bodies are quite brittle. I also walnut blasted the intake ports but they weren't too bad.

[ATinOf]

Worth adding it could also be the cam adjusters o-rings passing and leaking down into the valley; there are four one each end of the heads, and these can be done quite easily. When I had my engine out the valley was swimming; I did the four on the oil cooler, the oil filter housing as Ian suggests and the 4 cam adjusters and its been dry as a bone since. These cam adjusters sit in a recess so its easy to tell if these are the culprits.