Ok so i am driving around... no problems.. other then the car is running some what rough after HG replacement.. i attribute to needing a new O2 sensor.. some new plugs and wires... well i turn off the car.. and OIL PRESSURE SENDER is on the display... anyone?
check the connection of the oil pressure sender (on the side of the head, near the firewall, intake side). A new sensor is cheap (~$5) and you might want to grab a spare just in case.
I had the same problem on the wife's '91 535i after I reinstalled the head after a rebuild- but the sensor was leaking. The problem was- I forgot to remove the sensor from the head when I sent it to the machine shop- I think the sensor got damaged when the head was cleaned in the "hot tank", and it started leaking.
Bret.