I just put ~11 liters of Petrol in a Audi Q7 2008 with a tank capacity of 80l, I immediately filled it up with diesel and drove about 10 km to my hotel. Some sources say it’s fine if I keep topping it up, others say I’m screwed. Am I ok? Should I add oil?
Do not drive it at all!
Honestly, it’s likely fucked already but driving it more will ensure that. Gas is dry and will cause the high pressure pump to shed small slivers of metal that scatter through the injectors and lines. It was already a common failure on VAG diesels.
I’ve worked on many diesels that got filled with gas and the ones that get driven, even a little, have a near 100% fail rate.