Sounds like the pressure relief spring is getting stuck, so the pump can't build any oil pressure. As soon as you rev the engine, it unsticks & oil pressure comes back. It used to happen all the time with my race engines til i found a source of new oil pumps. So you can pull the pump apart & give it a could clean out, or fit a new oil pump.

Low oil pressure = ####ed oil pump! At least their easy to get at on a A series! Maybe get the oil pressure checked or do it yourself if you have a guage. Could be the wrong switch and coming on to early.

When you start it from cold does the light stay on for more then usual (5-10secs)?

the oil switch is rather new, only a few months. i did an oil change on it about a month ago. and the oil i use is the same as always. whats it mean if its low oil pressure, as in wat needs fixing? it also doesnt come on all the time, and as soon as you give it a lil rev it goes off

yeah that or the oil pressure switch could be stuffed also could be that the oil is 2 thick maby?

Ditto

low oil preasure

just been driven the ute around, and every now an then at low idle the oil light just comes on, there is plenty of oil and the filters new. what could cause this? its only the oil light