I have a 1997 Accord 2.2 vtec, I recently bought it and I'm stuck. When I got it, it had about 9qts of oil in the engine, so I drained and changed out the oil and filter with 5w-30. About 20 mins of driving the oil light came on, I stopped checked the oil and it was good. Started driving home and it stayed on under 1K rpms, then started blinking as I was driving.

Since the oil pump was whiny, I replaced the oil pump, replaced the oil pan gasket, valve cover gasket, distributor o-ring seal and oil pressure sensor and adjusted the valve lash. Changed the oil to 10w-30. I gave the whole engine a soak in engine decrease foam then with regular spray, I have no oil leaks at all.

The engine sounds healthy with no ticks or knocks all across the rpm range... BUT after driving for 15 miles or so and letting the engine warm up I get the oil psi light. First when I stop at low rpms then the blinking if I keep driving, still no ticks or knocks. What's next?

 

Hook up a pressure sensor to the oil system and verify the oil pressure.

 

That was my next step, I don't own one so I will try to get my hands on one. I'm just stumped because the engine sounds great, usually there are some kind of mechanical signs.