Fault Codes -2000 740i

[alinetobicoke]

The Check Engine light comes on usually after a highway drive of 100 km or more. It then goes off. The fault codes " Multiplicative Mixture Adaption - Bank1 and Bank 2" are recorded. I have changed the O2 sensor, plugs but it still repeats. There is no noticeable reduction in fuel economy and no symptoms when running.

Any suggestions?

[BAVARIANM]

Check for vacuum leaks around intake. It must be something that affects complete engine because you have faults for both banks

[hwade]

you might want to check the air flow meter