Some examples described herein may involve determining an advance timing window between the valve opening or closing and a designated time that the valve is scheduled to open or close; determining a closing velocity of the valve; monitoring an engine speed of the engine; determining valve lash information based on the advance timing window, the closing velocity, and the engine speed, wherein the valve lash information identifies a magnitude of the valve lash or whether the magnitude of the valve lash associated with the valve satisfies a threshold; and performing an action based on the valve lash information.