Firstly, thanks to those who answered my initial query re the T-VIS system (Kosh, Billwot, etc). I now have a follow-on question re the operation/ control of the system: The tech manual states that there should be vacuum at the actuator when revs are <4200, and no vac when revs are >4200; the same tech manual (in the FI section) also states that when revs are below 4200 there should be no voltage at the T-VIS pin of the ECU, and when revs >4200 there should be 10-14V. BUT, the valve near the actuator ONLY OPENS when voltage is applied, and therefore the actuator of the T-VIS will only receive vaccuum then (when there is voltage). Therefore, it will only receive vacuum when the revs are >4200 according to the FI section of the tech manual, yet that is when there should be NO vac, also according to the tech manual. So I'm confused. Please help, because I hate being confused!