the silver metal housing would be the egr valve, the metal pipe that goes down back of engine comes from exhaust manifold and I would blank it off so you get no exhaust gasses going back into engine (blanking plate) which can easily be made or bought. this will give you better fuel consumption
The inlet manifold - take off & give a good clean/de-grease as it will be full of crap and you will notice the difference once cleaned
if unsure do a search on blanking egr.
there is no mass air flow sensor as i know of only the mass actual pressure (map) sensor located in side of intercooler which i would also clean with electrical spray of somekind,
let me know how you go on as I have done all this with my much loved transit