The power button really doesn't have any "noticeable" effect on the transmission. It really just adjust the shift points of the transmission so that it shifts at higher RPM's (it's not like a turbo boost ), so it might be working just fine. Try turning the power mode off and getting on the skinny pedal when you take off from a light. Notice at what RPM the transmission is shifting, then put it in power mode and do the same test. Does the tranny shift at a different spot (higher up in the RPM band)?
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