Chances are the low oil sensor ( if oil injected) has failed, very common problem. There is a float in the oil tank that has a metal washer that comes off and drips to the bottom and triggers the alarm. There is a tricky repair available or replace the entire tank for big bucks. On mine, I just unplugged the oil alarm and every time I fill my 18 gallon fuel tank, I top off the oil tank.
Do some testing to be sure this is your problem, but on these 1992 oil injected engines the float failure is common. Get a factory service manual for your engine, it is well explained for you.
