What Causes High Engine Oil Pressure?
2 Answers
The reasons for high engine oil pressure are as follows: 1. Clogged oil fine filter: A dirty filter element in the oil fine filter can block the oil circuit, leading to excessive pressure in the main oil passage. Therefore, the oil fine filter should be cleaned regularly. 2. Pressure relief valve clogged or improperly adjusted: If the pressure relief valve is stuck by sludge, the oil pressure in the oil passage increases; if the pressure relief valve's spring is adjusted with excessive tension, the oil pressure cannot be relieved when it exceeds the specified value, resulting in excessively high oil pressure in the system. Thus, it is necessary not only to adjust the pressure relief valve according to specifications but also to clean it regularly. 3. Excessive oil viscosity: The viscosity of engine oil is related to the engine's temperature. When the temperature is too high, the viscosity decreases; conversely, it increases.
I've seen quite a few cases of high oil pressure while repairing cars, and there are usually several common reasons for this. For example, the viscosity of the oil is too high—using thick winter oil in summer can lead to poor flow and increased pressure. Blockages in the oil passages are also problematic, where debris accumulates in the filter or oil channels, obstructing oil flow. A stuck oil pump relief valve is particularly troublesome, as it should release pressure when it's too high but fails to do so. Another issue is faulty sensors giving false readings, misjudging normal pressure as high. Internal engine problems, like bearings with too little clearance, can also increase pressure. High pressure is harmful—it can burst oil seals, cause leaks, or even damage the engine block. I recommend car owners use oil with the right viscosity and avoid mixing brands to save money. Regularly changing the oil and filter prevents blockages. If you hear unusual noises or see warning lights, get it checked immediately—don't risk driving further. Safety first! Prevention is always better than major repairs later.
