A couple of times today, the oil light flashed on on my wife's car and then went away again. I checked the oil level first (which was fine), so took the engine cover off and noticed that the rocker cover gasket is weeping. Annoying, but not the end of the world - and as the car has enough oil, not the cause of the warning light. So I had a look at the pressure switch, and once I got the connector off, a few drops of oil came out - not right, right? The most troubling thing, though, is that the oil warning light DIDN'T come on when I started the engine with the switch disconnected?!?

Any ideas?

Oil pressure switch diaphram has started leaking. Light wont come on with switch disconnected, as it requires a short circuit across the wires e.g. when the switch is closed. Time for a new switch.

what he said above

Thanks for the explanation, gents! Will keep an eye on both leaks, and see if they can wait until the car's in for service in the New Year...