What are the potential causes of oil pressure drop?
Oil has a major role in sealing the combustion chamber during normal in-use vehicle operation. The oil pressure gauge reveals the effectiveness of this seal.
An abnormal drop in oil pressure can be explained either by a decrease in engine oil viscosity due to its dilution with fuel (problems in injectors or low load use ...) or simply by an insufficient amount of oil in the lubrication system (due to oil leak, or excessive oil consumption, or failure of the pump causing the oil to flow), or by mechanical parts wear.
If you experience any of these problems, seek professional advice!