engine lite came on

I had the same issue not too long ago. check to see if your vacuume lines are all connected properly. have you washed under the hood recently?

If its the check engine light that you are referring to, it could be anything.One of the problems I had with my '04 Optra5, was the gas filler cap.If its not properly secured the EVAP system will detect a small leak and light the Check Engine.You should twist the gas cap until you hear a clicking noise.After a couple of miles the light should come off. If this doesn't solve the problem, then you need to take your car to a dealer or other repair so that they can put a scanner and read the Diagnostic Trouble Codes.Then, you will know for sure what the problem is.