2001 Chevy Cavalier Engine light

Hi! My 01 Chevrolet cavalier has been showing the engine light going on intermittently. I have had it checked and there is nothing wrong with the engine. I have been told it is the sensor that has a problem and is typical for this car. I cannot get my car inspected this month if the light comes on. What should I do to fix the problem? Is it electrical? Should I take it to a specialist? Thanks so much. I am on a limited income and disabled at 66 so your help is much appreciated.