A combustion-powered, fastener-driving tool comprises a structure defining a combustion chamber and defining a driving piston cylinder, which has a wall and defines an axis. A nosepiece is mounted to said structure and communicates with the driving piston cylinder. A driving piston mounting a driving member is arranged to be axially driven within the wall of the driving piston cylinder upon combustion of a fuel in the combustion chamber, so as to drive the driving member from an uppermost position wherein the driving member is retracted from the nosepiece into a lowermost position wherein the driving member is extended into the nosepiece. A combusted gases-actuated mechanism is employed for feeding fasteners from a collated strip of fasteners individually and successively into the nosepiece. Combusted gases are diverted from the driving piston cylinder so as to actuate the feeding mechanism when the driving piston is driven. Combusted gases are taken in through the wall of the driving piston cylinder, at a location between the uppermost position of the driving piston and the position of the driving piston when combusted gases are exhausted through one or more ports in the wall of the driving piston cylinder.