ID these things please.

on the first pic i would guess that the oil pressure sensor is the one closest to the oil filter......and just trying to take a stab at it....i think the other sensor is a knock sensor. the knock sensor responds to spark knock caused by Pre-detonation of the Air/Fuel mixture.

on the second pic the big hole seems like its either a water passage or a heat tube....i would go with water passage bcoz it has a bolt hole by it so im guessing it would have an O-ring and a retainer bracket that goes there.

the two smaller holes look like bolt holes like some kind of bracket goes there........IDK....thats my guess