Hi all, I bought a complete MFI setup to go into my XR2. Im plodding along just ive found this sensor/valve on the back of the block, one pipe comes off and goes to the throttle body the other rubber pipe is just going off into nothing, also there is a union coming out of back of inlet mani and ive no idea where that goes either.

 

Both go on the inlet mate and its the aux air device, make sure you wire it all right as that has a 12v feed from fuel relay system the others are just thermo signals so have no live and will fry your sensors if plugged wrong