'84 - 240D, 255K

Changed oil 1.5 weeks ago - normal running before & after.

Yesterday on cold start - 8 lb pressure at idle instead of pegged. Went up to the peg when drive; sagged back to 5 lb at idle.

I thought maybe I left the old 0-ring in the filter housing - opened it up tonight -- no extra o-ring, nothing I could see or feel at the bottom of the housing. Put it back together with no filter, started it, same low pressure symptoms. Tried blowing in the open end of the center filter shaft -- could get a little oil out of the hole near the top if I blew really hard. Tried to chase the shaft with a cooking skewer that started in fine, but hit an obstruction maybe 2" in; feels like it was made that way. I have no access to compressed air at the moment.

Put the filter back in with a new o-ring & started it -- same symptoms. Oil is full (originally thought maybe the filter o-ring leaked, but no sign of that) with no sign of contamination.

Any ideas??

Sorry for the double post.