Abstract: A fuel injection nozzle of the inwardly opening type includes a switch means operable to provide a signal indicative of when the valve member of the nozzle is lifted from its seating to start fuel delivery. The switch means includes a first member secured in the housing of the nozzle, a second member movable with the valve member and a third member slidable on the first member to define a damping chamber into which the second member extends. The second member has a head which with a step defined by the third member forms the contacts of a switch. A spring biases the third member in the direction to close said contacts. When the valve member lifts from its seating the head separates from the step to open the contacts and the damping chamber restricts the movement of the third member to close the contacts.