What are the reasons for the high engine oil temperature in the BMW 5 Series?
2 Answers
BMW 5 Series high engine oil temperature reasons are as follows:1. Insufficient coolant: The engine cooling system lacks coolant, possibly due to leaks in the engine, such as water pump leakage, pipe damage, or radiator damage.2. Thermostat failure: A faulty thermostat in the engine cooling system causes high water temperature. Because the thermostat cannot open, the coolant flow inside the engine is obstructed, leading to excessively high coolant temperature.3. Cooling fan failure: The cooling fan in the engine cooling system is not functioning properly, resulting in poor coolant heat dissipation, illuminated water temperature light, and excessively high coolant temperature.4. Water pump failure: The water pump in the engine cooling system is malfunctioning, with poor rotation, leading to inadequate coolant flow, illuminated water temperature light, and excessively high coolant temperature.
Having driven a BMW 5 Series for many years, I've encountered several common causes of high engine oil temperature. The most frequent issues are insufficient oil or degraded oil quality, which reduces cooling efficiency. Another cause is problems with the cooling system, such as a clogged radiator or a faulty water pump, leading to inadequate heat dissipation. When the engine is under heavy load, like during long summer drives or uphill climbs, temperatures are more likely to spike. I recommend regularly checking the oil dipstick to ensure proper oil level and freshness, and also making sure the coolant is sufficient. If the dashboard warns of high temperature, stop the car immediately to let it cool down—avoid driving forcefully as it may damage internal engine components. Ignoring this issue can accelerate part wear and double repair costs. Prevention is key—maintain good driving habits and schedule regular maintenance.
