As I was driving our new 2016 Stingray home from Bowling Green a couple of weeks ago, I saw the little box on the economy screen with a "V4" in it and I was in Tour mode. Later on, when my dear wife was driving I read though the owner's manual and learned that the engine has an Active Fuel Management System that shuts down 4 cylinders when the engine senses that they are not needed. When we were going up a grade in 8th gear or when we were accelerating, the engine automatically kicked in the inactive 4 cylinders-I began to notice this, too, by feeling something like a shift in gears, but the tranny was staying in the 8th gear. When we cleared the grade or decelerated, the V4 returned.
The manual says that in Eco mode the inactive 4 cylinders are off full-time. At least that is what I understood.
Hope this helps.
