A flow-responsive diverting valve is particularly useful with pressure washers of the type having a water pump coupled to an internal combustion engine equipped with a pull-rope starter. The valve provides an "easy-start" feature and has a valving chamber and a fluid inlet and two fluid outlets. A magnet is fixed on the valve body and when fluid flows into the inlet at the low flow rate occurring when operating the starter, a valving device, e.g., a check ball, is restrained by the magnet. When fluid flows into the inlet at a higher flow rate (as when the engine is running and the pump is delivering water at a substantial rate), the device closes the first outlet and diverts water to the second outlet. A method for operating a pressure washer includes magnetically restraining the valving device away from the first outlet while operating the starter and then running the engine, thereby urging the device to close the first outlet.