Oil Light turns on, but oil level is fine?

Could be a bad oil level sensor.

It does indeed sound like low oil pressure, either from a faulty pump or worn bearings. Now, it depends on how much you are prepared to put into it, seeing how you seem to have given up on the car.

Personally I'd do two things, both relatively cheap but which might prolong its life. Replace the oil pressure sender switch, in case that's faulty, and change the oil for something thicker. Replace the filter too. If that does the trick, on you go. If not, don't waste time and money on anything else.

Could be a faulty oil pressure sensor switch causing the oil light to come on. About $15 for a new one.

It could be the sensor, not uncommon. I have had that but not ever a failed oil pump. But it could the oil pump is failing. But most of what you mention about the light is all normal, What is abnormal is wheat comes on while running.

BUT you;ve got to live your life. Just bring a magic marker and some material for signs.

The light has NOTHING to do with the oil LEVEL. It indicates low oil PRESSURE.

If the oil level is near or at the top mark on the dipstick replace the oil pressure warning light sending unit. They cost under $30. Do a search on youtube for how to replace it. They are a common problem.

if the light still comes on have a mechanic check the oil pressure.

Sounds like your oil sump pick up screen is plugged up, that motor is running on borrowed time my friend.

*Worn bearings / oil pump are the opposite, good oil pressure until the oil gets hot. You have a restriction

or see the video below on how to diagnose a broken / cracked oil pickup screen and tube assembly issue.

*I did a bit of research for you, it seems the 2 liter steel pickup tube stress cracks over time because the aluminum boxer block expands more under heat then the steel tube causing it to defect crack over time. If this is the case, simply pulling the oil pan and fixing the broken oil pickup assembly will fix your problems.

*The dealer is quite aware of this time stress cracking defect and they are hoping you will trade it in cheap before engine damage occurs so they can do a simple fix and sell it again for top resale $. I would never go back to that Subaru dealer again for service! Dealers are very dishonest in most cases, they are only good for warranty work. They are profit based, if they can get your old car at half BB value and know the simple fix, they will work you over on the sales grill pyre. This is why you do some research before going to the dealer service rep.

https://www.youtube.com/watch?v=7OokXhL-A5c

Hey! Guess what, Skippy... If you just want to keep the car until it dies, you'd better start shopping for a replacement because your poor little Subaru is on it's last legs. Don't count on driving back from that 300 mile road trip.

The OIL LIGHT indicates low OIL PRESSURE. NOT low oil level. If your oil level shows full and the oil light stays on, it's probable that your oil pump has failed.

When coolant gets into the oil in sufficient quantity and you drive the car, the oil will look like a chocolate milkshake. The oil light could be the pressure, not level. As the engine fails, the oil pressure will become less as parts wear out. I assume that is happening. Try using a thicker grade of oil.

If you don t change the oil filter when you change the oil, the filter could well be clogged, or the check valve stuck.

But, honestly... I think that there s something more seriously wrong with your engine.

Look under the oil filler cap: If there s a creamy substance that looks like chocolate milkshake, coolant is getting into the oil.

Look at the coolant recovery tank: If oil is getting into the coolant, you ll see oil stains through the plastic.