how do i ajust the idle speed on a 09 murano s?
You don't. It is programmed into the ECU from the factory to idle at a particular RPM due to ambient conditions and operational conditions of the engine. I.e. total run time, engine coolant temperature, ambient temperature, o2 sensor data, etc. If you were to get some sort of programming interface and means to program the already locked ECU than you plausibly could modify it but for what goal??
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