Coolant Leak & Oil in Induction Pipes

[craigs6124]

Hi everyone
I have a 2016 8v facelift with a coolant leak. It is coming from a plastic unit which is directly underneath the inlet manifold. Could anyone identify what the unit is from the attached photos, please?

Additionally, to gain access to see where the leak was coming from, I had to disconnect the induction hose that runs along the front of the engine, underneath, from the intercooler to the inlet manifold and found it had a good residue of engine oil in it! I guess this is very bad? Can anyone confirm? Turbo oil seals maybe?

Car is under warranty until September, so I'm hoping I can get them to do any repairs, but I would like to be armed with as much information as I can before I go to see them at the main dealer.

Thanks for reading

Craig

The first image is just to show the unit. The second is showing fresh coolant leaking. I appears to be coming from around the rectangular protrusion (with a chamfered edge)

 

[craigs6124]

Hello again

After a bit more searching online, I think I have found that it is the water pump/thermostat unit. I didn't expect this as I assumed the pump would be on the belt end (LHS) of the engine. Is it an electric unit, does anyone know?

 

[craigs6124]

Just found this.
https://www.audi-sport.net/xf/threads/⚠️all-s3-8v-owners-coolant-leak.344222/
Sounds like exactly the problem I'm having.
Also found this. . .

So it sounds like a small amount of oil in the induction pipes is normal.

I'm off to the main dealer tomorrow then.

 

[92683]

yeah bring it to the dealership to see if its covered under warranty.

 

[craigs6124]

All repaired under warranty. They replaced the "thermostat housing". I've not seen just the housing available to buy on its own, only along with the water pump. Not great that this has failed after only 13,000 miles and it is a common problem. I think this will be job I will have to tackle myself, in the future.

 

[92683]

the particular part has been an issue for most of the s3. they have said it is just a bad batch of parts, just like the in the 2015's the turbo was defective. you should not have any further issues other than normal wear.

 

[LonestarS3]

I have a '15 and my thermostat housing was replaced at 10K miles. I've read that some owner have had it replaced twice.

 

[92683]

twice! that is news to me but i wouldnt be surprised.

the real question is when i goes bad again will they still do it if its out of warranty?
on mine i can smell coolant still even after the repair work but the dealership guy still insist that its fine even when i said it smelled like coolant leak the first time.

 

[KenMoore]

Did they use the thermostat housing made of metal on your last replacement? I'm getting mine replace at 19500 miles under warranty and don't want the same crappy water pump put on if my warranty expires next year.

 

[92683]

im going back this week for them to rechcekc and fix whatever it might be again.