boost is correct it reads inputs and directly relates to how much fuel is delivered the iacv, tps, maf sensor all send inputs which are used to calculate fuel delivery but that is not the only thing needed to make it go put put it needs air which is what you will set with the idle screw or your throttle which is the air metering device. if you set idle slightly higher with the screw it wont effect anything except make it idle higher if its a ways off you may want to recalibrate the tps but all i have seen have been ok. the iacv valve im pretty sure is not even necessary most efi atv's dont even have one i will probably end up bypassing it when i finally get a chance to make up a TB i think it really acts more like an enrichment valve. i need to get some time and hook up an occiliscope and see what it effects it has