The letters VVEL are important to the architecture of Nissan engines. Those four letters stand for Variable Valve Event and Lift. What that refers to is a Nissan engine that operates without the use of a throttle body. Instead, the air flowing into the engine is metered by way of the cams and valves. It's a pretty trick system, and due to its complexity we're going to need some help from Engineering Explained host Jason Fenske to explain it all.
At the heart of the VVEL engine, it's all about offset and adjusting cams and other rotating pins and links that make this whole thing work. Air flows through the throttle opening that sits wide open instead of opening and closing as the driver depresses the pedal. This air is then allowed into the combustion chamber at a rate determined by the way the cams open the intake valves.
As Jason explains, VVEL and similar systems (BMW's Valvetronic, for instance) have three advantages. First, they reduce pumping losses because there is no throttle body to close off the airflow and create a vacuum. Second, they create quicker throttle response because the air sits right outside the combustion chamber. And third, they allow a higher cam profile, which creates more power.
There's still an actual throttle body present, but it serves as a fail safe in case part of the VVEL system decides to play games. It's not otherwise needed, though, and all of the air that your engine breathes finds its way into the engine in a manner described in great detail in the video above.