My understand is disabled Valvetronic is not mission critical nor damaging but the phase BMW likes to use applies: drive moderately.

On the N62 a very common diagnostic technique and workaround for badly running motor is to unplug the Valvetronic motors.

The N63 is the more touchy motor regarding oil flushes.

If my n55 started acting up I'd unplug the VT motor.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)