Nah, my money says that it's a little bit of something that is preventing full closure of the oil pump relief valve. At low engine speeds the pump does not provide much volume or pressure & it doesn't take much to bleed off enough extra pressure to bring it down into the 'light on' zone.
As revs pick up, the volume & pressure are enough to overcome the losses at this point.

Well, that's my theory anyway.

As for that back bearing thing in my engine, I suspect that it's a once in a lifetime problem.

yes the light stays on longer than normal when starting. im driving it on thursday, so i will see if it does it again, and if yes, i will print this off, and go talk 2 the mechanic. i think its a bet 2 much 4 to try fix

good luck, for me it's never one of those simple things.

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I've had a few cars with very high mileage do this with a dying oil pump, and have found that thick oil can actually help the problem... It will take a little longer to bring pressure up when you start the car, or you can give it a small blip on the throttle to get the pressure up, but the thicker oil hangs up in the engine better so the light doesn't come back on at idle once the pressure is up the first time. I generally use 40W70 for this kind of purpose (yes it's pretty hot here in Adelaide, so you probably don't want to try this in the winter in the US, or if you live in Thredbo or something!)

If it's an engine that you want to keep long term though, just get it checked out and fixed!

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Why did you replace the last oil pressure light switch? Same reason/symptom as now?

If it's not a dodgy new switch, I'm picking muck in the pressure relief valve keeping it from completely closing at low flow/idle (given these are exposed to unfiltered oil).

Time for a ca18det conversion

my engine did the same thing oil light took a while to go out. I did up the oil pump (parts still available from veale) including relief spring. helped a bit put a new sender on still the same. then i cranked the idle up to 900-1000 rpm oil light goes out pretty quick now a pretty dodgy thing to do but ive done 15000km since no worries and now ive turboed the engine and still havent had any troubles