Engine Mechanical problem
2004 Chevy Epica 6 cyl Front Wheel Drive Automatic 55000 miles

I have a 2004 Chev Epica. The oil light comes on after driving 10km and the car comes to a stop. When I press the gas or rev the engine at Park, the light goes off. Initally it will blink but now stays on after braking. No oil leaks. Change the oil regularly. The dealer changed the oil sensor twice. No codes on the computer. Help.