James Goddard

It appears that this is a drain hole through the block from the top near the turbo / oil cooler that drains down to the bottom of the block but doesn't actually enter the engine - assume it's to stop a build up of water / moisture on the top of the block. The extreme heat from the turbo dries out the seals on the oil cooler, causing the leak. The oil then flows through this drain channel and out at the bottom. It therefore appears to be leaking from this hole, when in fact it's leaking from the oil cooler at the top of the engine.

Massive thanks to Richard aka Spartacus 68 for recommending Tomas at VAG Technic who is very familiar with this problem and can fix it 🙂

Hi Cliff Thanks for the post - sadly, no plug in it and no-one including the manufacturer's technical department seems to know why it's there or what purpose it serves ... all ideas welcome.

And here's a photo of the 'hole' in the engine block - any thoughts would be really appreciated.

We've got a 2017 S4 Avant that went to the main dealer with a small oil leak. In their attempt to solve the leak, they completed a diagnosis, replaced the casings and seals around the timing chains, then replaced the sump ... then found a manufactured hole in the engine block that was leaking the oil ... and told us it now needs a new engine! Has anyone experienced any similar tragedy?