Synthetic Motor Oil, Oil Pressure Gauge, Not Enough Oil?
Looking at buying a used 83 Datsun 280ZX Turbo. Owner had the top end and turbo professionally rebuilt. He's using synthetic oil in the engine. He posted a video with a clear shot of the oil pressure gauge. When the car is idling, a square red light comes on next to the gauge indicating that there isn't enough oil in the engine. The owner said that this happens because synthetic oil doesn't tell the gauge that there is enough oil. When the engine is revved up, the light turns off.
I know that synthetic oil doesn't react to temperature changes like conventional motor oil. Is what he says true, or could there be another problem with the engine? There's no leaks coming from the engine and no smoke coming out of the exhaust.