Hot take: The guy down the street thinks engine oil doubles as salad dressing.

Topping off his crankcase with Italian vinaigrette is a bad move. That stuff is just oil and vinegar, not made for engines. Real engine oil has additives to lubricate parts and handle high heat. Vinegar can cause rust inside the motor, and the oil in dressing breaks down too fast. His engine could overheat or seize up from no proper lubrication. He needs to use actual motor oil for his car.