Being a curious man I purchased one of these and fitted it yesterday to my 3.0tdi, it restricts the flow of EGR gases, I know if it had been a plane blanking EML would have likely come on and that would be an MOT fail
but with the restrictor all is good, Initial response is it seems to have a better pick up, I will test the economy of it tomorrow, amazing the lengths they go to for emissions at the sacrifice of your engine
https://www.ebay.co.uk/itm/EGR-valve....c100005.m1851