Question

What does code P1161 mean on my 2001 BMW 740il?

Answer 1

P1161 BMW Code - Fuel Trim Adaptation Additive High Bank 2

Short Term Fuel Trim (STFT) is a value that indicates how the Engine Control Module (ECM) is adapting the factory programmed fuel map. This is used to govern the correct amount of fuel to inject.
The oxygen sensor is a key part of the fuel trim calculation. If the Oxygen sensor indicates a lean mixture, the STFT will be increased above the typical Value. If the Oxygen Sensor indicates a rich mixture the STFT will be reduced to below the typical Value.

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