the oil light comes on when you start the car but when you rev the engine it goes off but comes back on again when you stop reving
Engine & Drivetrain
The light comes on when the oil pressure is too low.
Check the oil level and top up if below minimum.
If this doesn't fix it I'd suggest an oil and filter change.
If this doesn't fix it I'd suggest the oil pump needs replacing.
If you drive with the oil light on you will probably damage the engine.
Most probably oil pressure warning light switch faulty