The present invention pertains to a process and a system for controlling the intake valves of an internal combustion engine comprising at least two valves per cylinder. During the closing of the intake valves of a cylinder, provisions are made for closing a first valve and then for closing a second valve, the time between the closing of the first valve and the closing of the second valve being such that it permits the propagation toward the second valve of at least one overpressure generated in the first port by the closing of the first valve.