A fuel injection nozzle of the inwardly opening type has a valve member (16) slidable in a bore (15) in a nozzle body which is secured to a holder (10). The valve member is biased by a first spring (21) into contact with a seating and is movable from the seating by fuel under pressure. An abutment rod (25) is engageable by the valve member after a predetermined movement of the valve member away from the seating. The abutment rod is biased by a second spring (27) housing in an insert (24) mounted in screw thread engagement within a bore in the holder. The rod extends through and is guided by an aperture (24A) in the insert and is further guided by guide means removed from the insert. The guide means can be a bush (23) carried by the holder, the coils of the first spring (21) or the valve member.