do what I did: you call them. tell them that when you arrive to drop off your car, you will then bring a tech along with you to show them how to reproduce it. that's it. don't leave until you have one of them there in the passenger seat when it happens. Make sure that they see the tach plummet to 0 with your clutch on the floor. Make it obvious.
I learned that after my first trip and they couldn't reproduce it on their own, after ~1 week holding it. Granted--that was earlier on and the stalling had basically stopped for me, as well. ...it didn't shock me. fast-forward 500-700 miles, and it was on like gangbusters. Maybe 25 stalls within 2 weeks, after making it easily reproduceable after a 10-15 min parking lock circuit of hard start/stops. Anyway, I was also fortunate with a shop that didn't ever give me pushback on this. ...though I did avoid a closer one that just wouldn't listen over the phone. Didn't even bother with those dudes, haha.
so after the 2nd drop-off, they called me back in 2 days, said they reset the ECU after speaking with VW, tested themselves (As per my instruction, lol), and said it was great. I told them I wouldn't sign off until I took it out myself, and they were cool with that. It's been flawless ever since, so 3k+ miles, summer and uh "winter" such that is around here right now...
I still haven't changed the oil, btw, but I'm just waiting for some more stuff to arrive in mail. I'm at 1.4k miles, but car just dinged one year on its official birthdate (1/19) and I'd rather make sure it gets swapped out in the 1 year time. ...yes, I've been slacking.
No, I don't believe this is really oil related (or fixable by oil--I think it's an ECU fix that makes a proper adjustment to oil-pressure readings or something...you know, something that simply replacing the oil could never actually fix) I do wonder, now, if I swap it to the 508 that I've ordered, fully assuming that this NA-made GTI was loaded up with regular Castrol 0w20 (at the time, I'm not sure that any 508 Castrol was commercially available?), that this non-508 to 508 swap will cause...issues.
Maybe I will even gain the 30 butt hps or something?
maybe?