My understanding is that many engines are designed to drain their oil via the dip stick hole using an oil extractor. I can find plenty of information on other models which seem to say it's fine (if not the standard way), but very little information on the CAVD (1.4 Twincharged 118TSI) specifically to confirm if this is possible.

I did buy an oil extractor kit to give it a bash, picked up the requisite oil and filter only to find out that the dip stick hole on the 118TSI is particularly narrow. The 6mm tube I have is too wide... by only a bit? A lot?

Has anyone actually done this?

VW have this kit for workshops, although I can find minimal information on the parts (or what models it's suitable for).
VAS6622A, Used Oil Collection and Extraction Unit - Audi Authorized Tools and Equipment

This page seems to say it's used on the CAVD:
https://www.kolhosniki.ru/elsaonline...#X-MUSDTRJWCWB

In theory that means one of these probes is the right one, but finding information on the kit itself and/or the individual probes is proving difficult.

Oil extraction probe, rigid: VAS 6622/1, ASE 417 166 00 000
Oil extraction probe, flexible: VAS 6622/2, ASE 417 167 00 000
Oil extraction probe, flexible: VAS 6622/3, ASE 417 168 00 000
Oil extraction probe, flexible: VAS 6622/4, ASE 417 169 00 000
Adapter for direct extraction: VAS 6622/5, ASE 417 170 00 000

Based on this one Ukrainian website:
VAS 6622/1, ASE 417 166 00 000 - The flexible dipstick for pumping out oil has a diameter of 6 mm and a length of 700 mm.
VAS 6622/2, ASE 417 167 00 000 - The flexible dipstick for pumping out oil has a diameter of 6 mm and a length of 700 mm.
VAS 6622/3, ASE 417 168 00 000 - The flexible oil dipstick has a diameter of 8 mm and a length of 700 mm.
VAS 6622/4, ASE 417 169 00 000 - The flexible oil extraction probe is equipped with a connecting element, which corresponds to the connection of the extraction hose and has a diameter of 7 mm and a length of 1000 mm.

Based on that 6mm would be correct...

Well, given I've written all this I figure I might as well keep going and post something.

So I re-measured the tube I have and it's ever so slightly out of round being just under 6mm in one dimension but just over in the other... given all of this I figured I'd try again, but with a little more force (while still being careful).

Yep. It's tight, but it does indeed go in and seem to bottom out about where I feel it should. It's too late and I don't want to work in the dark, so this is now a tomorrow problem, but it looks like in writing this post I have answered my own question.

I should be able to update tomorrow on if and how it worked.
I'm also installing an oil catch can, but more on that later too.