Valve actuation system comprising in-series lost motion components for use in cylinder deactivation and auxiliary valve actuations

A method of operating an internal combustion engine comprising a cylinder and at least one engine valve associated with the cylinder and further comprising a valve actuation motion source configured to provide a main valve actuation motion and an auxiliary valve actuation motion for actuating at least one engine valve via a valve actuation load path, the method further comprising:

• providing a lost motion subtracting mechanism arranged in the valve actuation load path and configured, in a first default operating state, to convey at least the main valve actuation motion and configured, in a first activated state, to lose the main valve actuation motion and the auxiliary valve actuation motion;
• providing a lost motion adding mechanism configured, in a second default operating state, to lose the auxiliary valve actuation motion and configured, in a second activated state, to convey the auxiliary valve actuation motion, wherein the lost motion adding mechanism is in series with the lost motion subtracting mechanism in the valve actuation load path at least during the second activated state;
• and
• operating the internal combustion engine in:
• a positive power mode in which the lost motion subtracting mechanism is in the first default operating state and the lost motion adding mechanism is in the second default operating state, or
• a deactivated mode in which the lost motion subtracting mechanism is in the first activated operating state and lost motion adding mechanism is in the second default operating state, or
• an auxiliary mode in which the lost motion subtracting mechanism is in the first default operating state and the lost motion adding mechanism is in the second activated operating state.