Prior to the Spanish Grand Prix, the FIA had announced that it was going to ban the use of the device that uses the flow of exhaust gases from an F1 car's engine to create downforce even when a driver's foot is not on the accelerator. The proposed ban never came into effect as the FIA could not agree upon an effective way to implement the ban. The ban could very well have lead to a shake up in F1's pecking order that is currently dominated by Red Bull Racing and Sebastian Vettel.
Kolles also claims to have the support of FIA's technical delegate Charlie Whiting on the matter. He argues that off-throttle blown diffusers fall under the category of moveable aerodynamic devices that have been banned in F1 since the end of the 1982 season since exhaust gases are generated due to the movement of valves and pistons of an engine.
The movement of the exhaust gases through the diffuser (which is fitted on the rear of a car) creates an area of low pressure under the car and literally sucks it to the surface of the road.