When the oil pressure alert on the dash comes on, it has a small margin of tolerance. It lights up often because the pressure drops and therefore the lubrication is deficient because the oil needs to enter under pressure between the parts to avoid their contact and their melting, normally the caps of the connecting rods.
In engines that are already with their tolerances outside of measurements due to use (wear), it is frequent that it starts at idle and, in that case, although the solution is to disarm, increasing the revolutions a little is a temporary palliative.
If the light bulb does not go out when accelerating, the thing is serious, unless the sensor is damaged, which can only be verified by installing a pressure gauge in the line and in the workshop where the car must be towed immediately so as not to take risks or putting a new one
This alert can occur when the engine is full of sludge, possibly created by poor engine handling at low revs or by doing many short trips during which the oil does not heat and evaporates the enemies coming from the combustion, fed by the ethanol from the gasoline.
That mud covers the intake of the pump and the ducts until the engine stops, normally simultaneously when the light bulb is turned on. To get an idea of the condition of the engine, remove the oil filler cap and try to feel the sides with your fingers (note, in the heat) and gauge for debris. The best thing is to remove the valve cover to have a better film.
Sometimes it happens that the light bulb flickers especially when cornering or hard braking. This indicates that the level is low and the pump runs out of oil when the carriage changes position when it is tilted.
Immediately top up the level and if you are out of the reach of buying the exact oil, temporarily add any motor oil to avoid problems. Because when the dashboard flashes, it is because the pump is no longer charging the system, but it may happen that, even if the alert does not trigger, in these low-level conditions the pressure is not stable or sufficient.
Some cars have oil condition analyzers and they turn on alerts when they find it bad and there are also those that check the level and there are even those without a dipstick. The oil, when it exists, is measured with the engine off in a flat place and after a while.
Keep in mind that if you remove the dipstick with the engine running, oil will splash out in the crankcase as it forms a cloud when it lubricates the pistons. Also, it doesn’t tell you anything because at that time there is little oil below and the rest is going around the engine.