The instrument panel should communicate directly to the oil pressure sensor on the engine. Assuming that your oil level is correct, the logical thing to do is to get that sensor changed to find out if your engine has low oil pressure or not. Firstly, though, find the sensor and give the connector a waggle while someone watches to see if it affects the warning light (ignition on, engine not turning). If there is a bad contact, driving over bumps can make the warning light flicker. If you've downloaded the manual, you should be able to locate the pressure switch on one of the diagrams. If you have any doubts, get a mechanic onto it as soon as possible.