Oil pressure warning light

[shadders]

56 plate vectra 1.8 vvt 40000 miles
After been stood over night or for a few hours the oil pressure warning light takes 3 to 4 seconds to go out, if i stop engine and then restart it goes out as the engine turns!
I changed oil filter to see if that was problem, but that didnt help, is there an anti drain back as the filter housing was not full when I took old oil filter out. Bought it 2 months ago from Citreon dealer, they say its a quirk of vvt engines and all is ok.
I'm not so sure, any thoughts?

[Celes]

What grade of oil are you using? Could be too thick for this weather!

[peter-gsi]

My car does that. Just keep an eye on the level and if need be top it up. Called the AA out they said could be a sensor playing up. If unsure take it to the dealer. get it looked at if it's under the warranty

[Redviper]

Mine does that as well, takes 3 - 4 seconds to go out once the engine has started, rest of the day (when engine is warm) no problem.

As long as the levels are always topped up, then I dont think it should be a problem. low oil pressure is only a concern if the engine is operating at high speed - but i dont think it is low pressure - just the way the sensor works.