This thread is way too much fun. There probably isn't a diesel rental car in Europe that hasn't run on gasoline after being filled at least once in its life by an American not aware tat most Euro rentals are diesel. Most of the guys I work with who often travel to Europe admit to doing it and nobody had had a problem. The primary thing is lack of lube to the fuel pump. Gasoline firing off early is not a huge problem because the fuel is being injected, not mixed with the incoming air. It's not like spraying ether into the intake where you then have spontaneous untamed ignition well before TDC. For our military machines part of the testing we must do is to run on various types of fuel not intended to be used but will be used on a battlefield in an emergency. Some of that stuff is highly volatile and I can't remember failing a test with our diesels. OP did what I would have done, get all of the fuel up to the pump out, fill with new fuel, start it up and run at an idle until it sound normal, and go to work. You said you didn't run long nor did you run hard. Gasoline does run hotter than diesel so it can cause damage. However, in the old days, some drivers actually did put a gallon or two of gasoline in their tank every 4 or 5 tans just to clean it up. Would I recommend it? Absolutely not. Did you permanently damage it? Highly unlikely if you did as you said. In Europe it's almost impossible to put diesel in a gasoline car due to the filler size. I did, however, mistakenly put pre-mixed gas in my new BMW, I believe a 50:1 gas oil ratio. In Germany where before the 2 cycle Trebant was THE car. I was half asleep and put in 11 liters before I realized what I was doing. I had visions of ruining all the sensors with that highly polluting fuel mix but I filled the rest with regular fuel and filled more frequently than necessary to dilute the oil. The car is now 4 years old and still runs fine. No error codes ever showed up.