Viano Diesel Oil Pressure Warning and Engine Noise

Low oil pressure and engine noise on a diesel at that mileage sounds familiar. I had a similar issue on an older BMW 5 series, though symptoms can be misleading. Have you checked for oil leakage? An oil change won't fix a failing pump. Have you considered the oil pressure sensor? They can be faulty. What kind of oil have you been using? High mileage can thin out the oil. Have you checked the engine bearings?

Thanks for the quick reply. I didn't see any oil leakage. Is there a way to check the oil pressure sensor? What happens to oil pressure if the engine bearings are worn?

A faulty oil pressure sensor is difficult to diagnose without equipment. Check the actual oil pressure with a mechanical gauge and compare it to the sensor reading. Worn engine bearings increase internal clearances, allowing more oil to escape, reducing oil pressure. If the bearings are worn, the oil pump may not keep up, especially at lower speeds. A workshop can properly diagnose the cause.

Thanks for the explanation. I consulted a mechanic. It was an oil pump failure, and I had it replaced. The cost was 755€. Thanks again for your help.