The third model generation of the BMW 3 Series was launched on the market in the autumn of 1990 initially as a four-door sedan. Alongside the four-cylinder models BMW 316i and 318i, the six-cylinder models BMW 320i and 325i made their debut at the same time with four-valve engineering. The engines were already familiar from the BMW 5 Series but they had been revised for installation in the new BMW 3 Series. The BMW 320i now generated power of 150 hp from a displacement of 2 litres and was to become the best-selling six-cylinder model.