What are the causes of high engine oil pressure?

[VonArthur]

Engine oil pressure is high due to: 1. Excessive oil viscosity; 2. Malfunction of the oil passage pressure relief valve; 3. Blockage of the main and auxiliary oil passages to lubrication surfaces; 4. Clogged auxiliary oil passage nozzles; 5. Newly fitted crankshaft bearings, connecting rod bearings, or camshaft bearings with excessively small clearances; 6. Improper adjustment of the oil pressure relief valve; 7. Oil passages blocked by excessively dirty oil; 8. Short circuit in the oil pressure gauge or sensor. The causes of insufficient engine oil pressure are: 1. Lack of engine lubricating oil; 2. Clogged oil pump screen; 3. Faulty pressure relief valve; 4. Clogged oil filter; 5. Blockage or cracking in the engine cylinder head or block; 6. Excessive clearance in the engine crankshaft, camshaft, or connecting rod main bearings.