Peugeot 206 diesel fuel consumption stalling smoke

Greetings. The symptoms you describe, specifically the elevated fuel consumption, engine stalling during idle, the activation of the check engine light, and the emission of smoke upon acceleration, do indeed suggest a potential malfunction within the mass air flow (MAF) sensor system. Have you inspected your air filter recently? A clogged or dirty air filter can disrupt the airflow and negatively impact the MAF sensor's readings, potentially causing it to report inaccurate data to the engine control unit (ECU). This incorrect data can then lead to the issues you are experiencing.

Thanks for the reply! I did check the air filter about a month ago, and it seemed alright. Could it still be the MAF even if the filter looks okay? And if it is the MAF sensor, is there any way to test it before I go buying a new one?

Given that the air filter appears to be in satisfactory condition, it is certainly plausible that the MAF sensor itself is the primary source of the observed anomalies. While diagnostic procedures for MAF sensors can be intricate and necessitate specialized equipment, the constellation of symptoms points towards its potential dysfunction. Considering the vehicle's age and mileage, in conjunction with the diagnostic challenges, it would be prudent to consult a qualified automotive technician for a comprehensive assessment of the engine management system. Replacing the MAF without proper validation could result in unnecessary expenditure and the persistence of the underlying issue. I recommend taking your Peugeot to a workshop.

Thanks a bunch for the detailed advice! I took it to the shop as you suggested. They confirmed it was the MAF sensor. Cost me 365€ all in to get it sorted, but now it's running smooth again. Really appreciate the help!