Changed oil yesterday. Quaker 5W-30 full synthetic with AC PF63 filter. Initial starup at idle--10-15 psi. AFter idling 10 minutes, oil pressure climbed to 30 psi.

I removed the screen below the oil pressure sensor and noted that it is clean, so I reinstalled it and did the starup as described above.

I've noticed previously that oil pressure does rise from 10-15 psi to 40 psi at about 1000 rpm.

Very puzzling.