I recently encountered the P1118 code on my BMW, and it turned out to be a faulty MAF sensor. At first, I noticed rough idling and higher fuel consumption. After cleaning the sensor, the issue temporarily disappeared, but the code came back after a few days. Ended up replacing the sensor, and now everything runs smoothly. If anyone is facing the same problem, I recommend checking the wiring as well!

The Mass Air Flow (MAF) sensor for engine bank 2 is reporting unusually high air flow readings, which may affect engine performance.

DTC P1118 BMW