Outer Limits 4x4 Board

Driving to work this morning I was on the freeway doing 100kph, On Cruse Control, car lost a little power for a second then went along fine. Looking in my revision mirror there was a BIG puff of smoke left. Then looked at the Oil Pressure gauge to see it dropping. I pulled over & the gauge dropped to nothing.

Turned it off & let sit for a few mins then started again & accelerated, but the oil pressure didnt budge. So its been off since.

No oil looks like its leaking from the engine anywhere.

Anyone seen the oil pressure just stop like this before? If not its off to a Mechanic

i have watched the oil pressure drop to nothing before, then come back up to normal about a min later, and its happened maybe 3 times in the 3 weeks iv had it.... but it has always come back up again, so i think its just a dickie sender...