Quote Originally Posted by Simple aveo View Post
My oil light keeps coming on n off, it goes away as I drive but at a red light it comes on. How hard would it be to change the oil sensor n the rear main seal?
The condition that you are describing is very common to most Asian cars made in the past few decades.

If you have no oil leak, it sounds like it's a bad oil pressure switch. (The switch sends a signal to the light on your dashboard.) It's a cheap part and an easy one to change. Do that before you do anything else and it may solve your problem.