The injectors are not PWM pr say but you COULD call it that if you squint really hard at it. The frequency in that respect would be variable at half of the engines RPM (it squirts once every two revolutions). And the pulsewidth would be variable too cause the injectors are held open for different lenghts of time... No, lets just NOT call the injectors PWM-driven. They are actually just on/off. The idle valve and PS valve on the other hand...