I have spent the last couple of days researching Injectors and sharpening up my knowledge of size/use/Pros/Cons, however, i am at the stage now where i need gentle direction to my dilemma.   I also see an issue with the Zed, a reason to dive deeper into the unknown (for me anyway) and see it as a self teaching experience.   I have a slight knock/tick sound intermittently at idle and know its either one or a combination of Plugs/Coil pack/MAF/throttle body/Injectors.