A control system for an engine includes an valve actuator, a cylinder pressure module, and a valve control module. The valve actuator opens a valve of a cylinder at a first target opening timing during a first combustion cycle of the cylinder. The cylinder pressure module receives a cylinder pressure measured by a cylinder pressure sensor of the cylinder and, at a predetermined crankshaft angle after the valve opens during the first combustion cycle, sets a valve opening pressure equal to the cylinder pressure. The valve control module receives a reference cylinder pressure and generates a second target opening timing for a second combustion cycle of the cylinder based on the valve opening pressure and the reference cylinder pressure. The second combustion cycle is after the first combustion cycle. During the second combustion cycle, the valve actuator opens the valve at the second target opening timing.