Low Oil Pressure Trouble Shooting
It is also possible that the oil pressure gauge itself is faulty and not able to sense the oil pressure accurately. This is, of course, something that you can only say with confidence after going to a professional. That said, if you have checked that the oil level is ok and the engine isn't vibrating or heating up extensively, then the problem may be a defective oil pressure gauge. Now, it is true that the oil pressure gauge defects occur very rarely, but they happen enough times that you should consider them a strong possibility.