The sports car, believed to be worth more than €2m (£1.7m), was eventually located after the theft by a man posing as a buyer.
He is still being hunted.
Police in Dusseldorf said the thief was answering an advertisement for the red Ferrari 288 GTO, first registered in 1985, and turned up for a scheduled appointment with the seller in the western German city on Monday.
The pair went on a test drive, but when the seller got out of the car to let the man sit in the driver’s seat, he sped off.
Police have appealed to the public for information.