Oil pressure light comes on after warmup ?

You could replace the sensor with an OEM part and see if that helps .

Check the oil pressure to make sure what you've got. You might just need to change the pressure sensor, but it could be something else. The car's twenty years old and it might be a problem in the pump/lubrication system.

Yes by all means test the oil pressure, if the engine is worn the oil pressure will drop as the engine warms up. A oil pressure sensor is not the same as an oil pressure sender, a sender is for the gauge and a sensor is for the computer. On some vehicles if the computer doesn't see oil pressure it will not turn on the fuel pump.

I meant to say how do I check the oil pressure myself?

Get an analog gauge from most any parts store, if this is going to be a temporary install then just remove the oil pressure sender and install The gauge with the hardware kit provided in the package. Then start the engine and check for leaks. If none are found then you can proceed with the pressure test. If your going to make it permanent install then you will need a gauge mount and adapters so you can run both the gauge and the oil pressure sender.

Could be an early warning sign of worn out bearings. In other words, time for a new vehicle. Jim

It's an 04 Sebring. Count your blessings it lasted this long. Those motors were never considered well built longevity engines. Sell it while the market is hot and buy a Toyota