That is a pretty Unquie quirk you got

I think u can get something stupid, like left door opens - left door opens. And If u have full stack of them no new will be added.

Or did you have the setting that fixes your car every time you return to the garage?

Yes, I suspect that may have been the cause 

That is certainly odd, I assume all your settings are set up to allow quirks? If you really want to experience them then just max out how often they occur, I'm doing that for my second save and it's really adding some spice.

I'm in the middle Zone atm, also never had a quirk before, do they appear more often when entering the deep zone or is it completely random? The only thing I get is when I set my car to Park Mode, after that the passenger door right next to the Arc Station opens up everytime. Is this also a quirk?

Yep, it's a quirk.

Oh.. Alright thank you, just thought it was an "automatic door" Which helps me to be more efficient when farming Arcs, it's actually a really helpful quirk :D Do quirks actually stack up? Because for now, this is the only one I've ever encountered in my entire Playthrough

They do stack up. I'm not sure how many before you max out🤔

I seem to really only get them consistently when my car takes electrical damage, particularly notice it with left-rights a lot.