what are these for

[alliston]

just been looking around my throttle body and noticed this




then I found this pipe near it with a screw in

any one know what this is for













also found this pipe running along the back of the engine bay it runs from under the fuse box around to the fuel filter







then as I looked at the fuel filter there seamed to be another nipple without anything


anything wrong with this or .......

cheers

[Bogus]

First 3 pics look to me like theres been a boost gauge fitted at some point.
Pic 4 is just the fuel filter water drain.

[stormforce]

thats the egr blocked off and then like Bogus says