My oil light flickers My oil light flickers My oil light flickers: Oil level may be low. Check and refill to correct level. Oil may be of wrong grade. Check for correct grade of oil. Refer to handbook or bring vehicle in for inspection. Oil sending unit may be defective. Test sending unit and replace if faulty. Oil pickup screen may be clogged. Remove oil pan and replace or clean screen. Crankshaft bearings or oil pump are worn. This is a especially likely cause if the oil light only flickers when the vehicle is warmed up and idling in gear.