A method of operating an inkjet printhead having a plurality of ink chambers, each ink chamber including a heater element for generating a bubble and causing ejection of ink droplets from a nozzle defined in the ink chamber. The method includes the steps of: operating the printhead in a normal printing mode whereby relatively shorter drive pulses are delivered to the heater elements to eject ink droplets used in normal printing; and operating the printhead in a maintenance mode whereby relatively longer drive pulses are delivered to the heater elements. The relatively longer drive pulses generate high impulse bubbles for recovering nozzles affected by decap.