BMW M4 COUPE Owner's Manual page 179

Fuel Mobility
gine deposits, it is highly recommended to
purchase gasoline from Top Tier retailers.
Failure to comply with these recommendations
may result in the need for unscheduled main‐
tenance.◀
Recommended fuel grade
BMW recommends AKI 93.
Minimum fuel grade
BMW recommends AKI 91.
If you use gasoline with this minimum AKI Rat‐
ing, the engine may produce knocking sounds
when starting at high outside temperatures.
This has no effect on the engine life.
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