2008 Chevrolet Aveo Oil pressure light

It could be a few things, such as simply low oil pressure. However, if there are no noises from the engine such as ticking or knocking and the oil is clean and full, most commonly the oil pressure switch is bad. It is an electrical switch /. sensor which screws in the engine and closes or opens a circuit based on pressure. Many times they get corroded and malfunction or they begin to leak allowing pressure to escape. If you see an oil leak, chances are if you look it will be the sensor.

If everything mentioned is good, then I recommend getting a mechanical pressure tester. All you do is remove the oil pressure switch from the engine and screw in the mechanical one. Once installed, start the engine and see how much pressure there actually is at an idle. It should be between 10 and 30 psi at idle and build as rpm's increase.

Let me know what you find or if you have other questions.