Background - My friend's 245DL with 188k had what he thought was a bad rear main seal leak, so he parked it for 18 months until he could get time to look at it. I finally offered to help him do the job over my Christmas break. As I undid the clamp on the transmission cooler lines, fluid started to bubble from a crack in the tubing. So that was probably the source of the oil. But we did the rear main seal anyway, along with the transmission input seal. We put in new plugs, cap, rotor and wires, squirted a bit of oil in each cylinder, and when it was back together, it started right up. After idling for about five minutes, I noticed the oil pressure warning light had come on. We shut it down and changed the oil and filter. When the filter came off, there was little or no oil in it. We also tested the oil pressure sender per Bentley instructions, and it checked ok. We restarted it, and the light stayed out. So we test drove it, and in two miles, the light came on again. The car got towed home.

Before the car was parked, the engine never exhibited this problem. It had fairly good maintenance and I have no reason to think the oil pump is going bad. Could the oil that sat in it for the 18 months have solidified enough in the oil passages that they are partially blocked? Could a loose or worn oil sender wire cause this warning light behavior? Could the sender be intermittently bad? Any other ideas?

We haven't put a oil pressure guage on it to get a reading, but will do that soon and post the reading.

If the oil passages are clogged, what's the recommendation about flushing the engine to clean them?

Thanks in advance for any help.
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Jim Egelston - Seattle - '81 245DL, '85 244GL, '94 945T, '89 535i, '74 R90S