To be quite honest, David, I’m also struggling to find very much information. Such units have apparently been used on PSA Peugeot-Citroën engines for some years, in various different forms. Once they were cable operated, now they are motorised. As I understand it, the throttle body plays a vital part in the exhaust gas recirculation (EGR) process, by using a powered butterfly valve to control the intake of fresh air, according to instructions from various engine condition sensors. These days, high exhaust gas recirculation rates are required at times to minimise NOx emissions, and these high rates can only be achieved by precise control of intake air, and by reducing the ingested fresh air and at the same time increasing the volume of recycled exhaust gas. Such throttle valves are often also used at engine shut-down, to reduce engine shudder, and also, I gather, are sometimes employed during particulate filter regeneration. That’s about all I can tell you Dave, but maybe that’s quite enough.