Well, not exactly on my Mk7, but it's a MQB car (and I need a place to rant), so here we go.
My wife's A3 e-tron started making some kind of droning noise - stayed the same pitch, didn't seem to be related to tires (stayed the same regardless of brand new or old degraded pavement). Checked wheel bearings - near silent. Axles seem fine - car only has 65K km on it.
As much as I wanted to think it wasn't the case, it sure sounded to me like the electric drivetrain was making some noise....but that's impossible, right?
A quick digression: Car was bought with AudiCare, and the last of those services (at ~45K km back in 2020) included a DSG service. So, why not - it's like 25K km early, but saves me having to do it in a couple years.
So - changing the oil the other day, I noticed a little wetness around one of the DSG's drain plugs. Wiped it off, let the car sit overnight with the belly pan off and sure enough - nice little oil spot on the driveway. Pull out the Snap-on digital torque wrench and set it to the 45Nm spec for that plug - easily get another 30° or so before it beeps/buzzes.
So now, I'm realizing how long this thing has probably been slow-leaking (never left spots on our driveway, but the belly pan did have some dampness) and thinking....this can't be good.
Pull out the DSG fill equipment and figure I'll pump in 1L and see how much drains back out. If it's close to that same 1.0L, non-issue.
Start the car, open the fill plug....nothing comes out. Usually there's a little residual stuff in the fill pipe, but this was literally a few drops around the sealing edge of the plug.
Pump this in.
Let it spin for a bit. Then this much comes out.
(Had the wrong scale facing the camera there, but it's looking across to the other side of the container, you can see it's a little under 300mL)
So, in a car where the DSG fluid level is so finicky that not only does the car have to be perfectly level, but has to be within a 20°C temperature range (between 20-40°C...mine was right at 30°C), I was down over 700mL.
Now here's the kicker: Not only is the DSG the transmission on this car, but that
0DD transmission also houses the hybrid drive system for the car (which I take to mean, that's where the electric motor resides).
Just on a hunch, when I tightened that drain plug, I initially set my torque wrench at 30Nm (which is the oil drain plug spec), then tightened it to the spec 45Nm and sure enough - that felt identical to what my initial check of the tightness of that plug was. So, not too difficult to figure out how and what the mistake was.
A message containing much of the info in this post was sent to the dealership that did the DSG service; they've received it and are "reviewing".
So yeah - that's what happened with my car today.