BMW Repair Questions? Ask a Mechanic for Answers ASAP
the maf and the airflow sensor are the most common causes of poor fuel consumption so these are your prime suspects - also change the air filter if it is old
a proper scan on a high end scan tool that can read live data can reveal the cause with certainty
a new maf does not require coding
Sorry if you were hoping for a different answer, please don't shoot the messenger - I can only give the honest answer, which I have. Please remember that a low rating PUNISHES me for my honest and prompt response, and I receive nothing for my time and answer until a positive rating is clicked.Please let me know if you have further questions. Please do not forget to click a positive rating as this is the only way I receive credit for my answer, thank you. Best wishes with your vehicle.
Thanks for the advice, I rather thought a trip to the garage for a diagnostic check would be needed - I was hoping to avoid the cost!