Here is a good one for you to figure out. I have a 2001 concorde 2.7. We have just done a complete rebuild on this motor including new oil pump and pick up tube. Crank was turned .010 on both the rods and the mains. All new gaskets, water pump and timing components. Got the engine running yesterday and it runs great!! I took it for a test drive and the oil pressure light came on. I figure a bad sender, replace it and put a manual guage on it just to be sure. Start it back up and we have 25 lbs of oil pressure at idle. Here is the problem, if I let the car sit and idle up to operating temp or run it at higher RPM's the oil pressure starts to fall off to about 5 to 7 lbs of pressure. If I shut the car off and start it back up right away, I am back to my 25 to 30 lbs of oil pressure at idle or if you rev the engine up the oil pressure climbs accordingly and there is absolutly no engine noise at all. Does anybody have any ideas??? I am really stumped on this one.