The oil life meter was only on the FWD Caddies of that year and years prior. There was a fuel economy guage with all sorts of features and pressing two buttons showed oil life in a percent, but you had to reset it after every oil change, since it ran off mileage, not a sensor. I don't think the RWD Cads had such a computer (after '85 atleast), so the pedal pumping is the best option I think. Remember this car has the sensor-controlled idiot light, not the gauge. And if something hadn't been reset, then the light would have been on since the oil change, but it just now came on. That tells me there is just a glitch and the pedal reset method should set you off clean.
Greg