Coolant leak

[R7mol]

Hi guys, recently bought a a6 c8 with 84k on the clock. After a short drive today had an engine coolant low warning. Checked coolant level and it’s really low, noticed residue below the engine. Any ideas? Thank you 

[cliffcoggin]

At the risk of stating the obvious, there is a leak that needs to be traced and fixed. Have you looked to see where it is coming out?

If you bought it from a dealer in the last month take it back for a free repair or refund.

[R7mol]

The leak appears to be coming from the block. 
 

unfortunately it was bought private and the seller is not responding.

[cliffcoggin]

The cleanliness, part numbering and yellow paint suggest the engine has been newly rebuilt.

Unfortunately as a private sale the vendor has little obligation to fix the leak unless you can show written evidence that he has deceived you regarding the engine condition.