A standard BMW 6-cylinder engine with 4 valves was converted for methanol flexible fuel operation. New performance characteristics of air/fuel mixture and ignition timing were determined for different methanol concentrations (M20, M50, M85). The recognition of the methanol concentration was made by means of a capacitive alcohol sensor and the adaptive Lambda Control. Without any modification of the catalyst the HC emission was reduced about 40% in US-test cycle. The efficiency of M85 was upgraded about 8% under vehicle operation conditions. Under any method concentration the driveability of the car was as well as operated with pure gasoline. Operating with M85 the engine increased torque and power by 11%. (orig.).