What does it say about about me (or about Audi) that my gut reaction to red low oil pressure warnings animating themselves in glaring red on the instrument panel is to blame and replace the sensor?
Surely the sensor is bad. It's old. It's like a fuse. If the engine hasn't given up the ghost after twenty years and 257,000 miles, why would something go wrong now? A replacement sensor was five bucks. I'll tell you if it was the culprit a little later on.
Failing that test, the next is to get an oil pressure gauge and check it out. Thirty-five bucks on Amazon, or Autozone can loan me one.
Should it fail that test, I may achieve my Uncle Jim's dream of killing a modern car engine through benign neglect.
Edited to add:
One hour later, I'd removed the airbox to get at the old sensor, tucked away as it was under the exhaust manifold. I practiced a little patience with a crescent wrench (who has a 24mm open end wrench?) and it came smoothly off. It replacement went smoothly on. I buttoned her back up, double-checked everything and went for a drive.
Rev the engine, no error light. Up the drive way, no error light. Up the road, no light. Romped on her up to 60 a few times, no light. Drove her in to town and got some gas, no light.
Fifteen miles later, no light.
I love it when it's the sensor!