What's this?
 

Probably a stupid question but what is this under the throttle body on my inlet manifold? Looks like some type of valve?

Looks like a air temp sensor, usually fitted when running mafless??? helps the ecu calculate air density!!

Usually people(myself included) have them fitted to the intercooler pipes when running a FMIC, but maybe previous owner kept the TMIC and so was drilled into the inlet instead!!!

its the PCV, Positive crankcase ventilation valve, It draws gasses/vapour out of the crankcase when off boost and cruising. when boosting slams shut to prevent it pressurising the crankcase