can anyone help me wat is the oil pressure gauge meant to be reading on idol? and after i give it a descent boost the oil pressure seems to drop close too zero but if u turn the car off and on again it idols at 2??? culd it be a dodgy gauge?

Yep, it could be. The stock oil sending unit and gauge are not that reliable.

Oil senders are completely unreliable. They are also used in the GTiR Pulsar which has the same problem, a lot :(

Nissan dealer charges an arm and a leg for them