What are the reasons for low oil pressure in a car engine?
3 Answers
Reasons for low oil pressure in a car engine: 1. When the vehicle's oil level is insufficient, it results in a lack of oil available in the engine, leading to low oil pressure. In this case, simply adding oil to meet the specified standard is sufficient; 2. If impurities are present in the oil, they can clog the oil delivery pipes, causing low oil pressure. In this situation, the oil should be replaced; 3. When the oil is too thin, its viscosity significantly decreases, making it easier for the oil to leak through the gaps between various components, resulting in low oil pressure. In this scenario, the oil should be replaced or a thicker oil should be added.
I've encountered the engine oil pressure warning light coming on multiple times while driving, which always gives me a scare and prompts me to investigate the cause. My first suspicion is usually insufficient oil—maybe I forgot to change it or there's a leak under the car, so I have to crawl under and check. If the oil filter is clogged, the oil flow gets blocked, and pressure can't build up. A worn or faulty oil pump that doesn't pump enough oil can also cause a pressure drop. Worse yet, excessive bearing clearance leads to rapid oil leakage, making the engine prone to overheating and severe damage. That's why regular maintenance is crucial—I check the oil level and change it every 5,000 kilometers to prevent minor issues from turning into major repairs. Never ignore dashboard warning lights; pulling over to inspect can save you a fortune.
Having worked in this car repair business for years, low oil pressure is often caused by these factors. The most common is low oil level, which can be checked with a dipstick. If the filter is severely clogged, blocking the oil passages, the pressure naturally drops. The oil pump is the core component; wear or damage will cause loss of pressure. Excessive bearing wear with large gaps also fails to retain oil. Additionally, changes in oil viscosity, such as fuel dilution or degradation, can't sustain the pressure. During inspection, first use a pressure gauge for diagnosis instead of blindly replacing parts. Troubleshoot step by step—first check the oil level, then dismantle the pump to inspect for wear—this saves both money and time.
