S3 2017 coolant leak from top rear of engine

Most likely thermostat/water pump housing.
it’s a known fault. Have a search for thermostat housing or something like that. Multiple threads on this.

Sorry I didn’t see this earlier, I have seen this mentioned a few times before so you’re not alone. I have seen a metal replacement part for this, I’ll see if I can find any links even though you’re sorted.

danger S3 said:

Hi Everyone,

i just got this car in 6 months ago and it sprung a coolant leak today.
the leak looks like it's coming from the back of the engine up near the top where the coolant return pipe goes into the engine.
The video below shows the coolant boiling away at the back of the engine:


i think it's coming from where this hose connects to the engine:
View attachment 268402

is that a common issue?
or is there something else that it's likely to be that I haven't seen yet?
if so does anyone know what the part numbers are that are needed?

Sorry if this has been asked before but i couldnt find this specific leak.
Thanks very much for responses

Click to expand...

It's a late post, but hopefully it will help others searching for the same symptoms without shelling out hundreds for a water pump, or thermostat housing etc.

Just bough a 2016 S3 8V and had the exact same symptoms as above. I think the previous owner stuck some Radweld in and got rid pretty quick thinking worst case scenario; I was a little cautious when I bought the car as he had only had it 3 months...

If steam is coming from the back of the engine due to coolant dropping onto the cat and turbo then this is worth a go before shelling out £££.

The part number is 06K-121-143 (coolant adapter / flange and can be purchased at your local Audi main dealer for £6.60. It takes approximately 10 minutes to fit, or probably 30 seconds if you know what you are doing.

Thanks to everyone in this thread, as I would have never guessed it was just a £6.60 repair. I was expecting the worst!

Noted... many thanks for the tip ...