What's Causing Your Car's Oil Loss? 3 Symptoms To Investigate

Posted on: 4 May 2023

If you drive a car with a few miles on the odometer, oil loss will eventually become a fact of life. While oil leaks can be common, you don't need to live with this frustrating problem. More importantly, solving your oil loss issues will help protect your engine by eliminating the possibility of a catastrophic loss of engine oil pressure.

There are numerous reasons for oil loss, but the symptoms you're experiencing can help you begin to investigate the problem. This guide will discuss three important clues to help you determine the source of your oil loss to track down and eliminate this frustrating and potentially dangerous problem.

1. Visible Engine Bay Smoke

Smoke rising from your engine bay is not a sight that any driver wants to see. Do visible plumes of smoke and the acrid smell of burning oil mean your engine is on fire? Probably not, although you should never continue driving if you can see smoke. Once you notice this symptom, always pull over and confirm that there's not a more serious problem afoot.

Assuming there's no fire under your hood, a valve cover gasket leak is the most likely source of oily smoke. On many inline 6-cylinder engines, such as those used across a range of BMW models, the engine's orientation can cause oil from a valve cover gasket leak to drip onto the exhaust manifold. The oil will burn off and produce visible smoke when it hits the extremely hot manifold surface.

2. Splattered Oil

Another frightening symptom you might experience alongside oil loss is visible evidence of splattered oil across your engine bay. While numerous catastrophic engine problems may result in oil exploding under your hood, there are also some minor culprits. Assuming you're only losing small amounts of oil, the most likely explanation is that oil is dripping onto an accessory belt and splattering everywhere.

On some engines, the position of the oil filter housing gasket or oil cooler gasket can allow oil to drip directly onto the accessory belt. In addition to ruining the belt and potentially even causing it to slip off, this problem will quickly make a mess of your engine bay. Even if you aren't losing much oil, you should address this problem quickly to avoid damaging your car's accessory belt system.

3. Vanishing Oil

What if you don't have any evidence of an oil leak, but you're still losing oil? Unfortunately, the answer is often that oil is entering your combustion chamber and burning off. Internal engine problems, such as worn piston rings, can allow some oil to seep past. Note that a little oil loss may be normal if you use an extended oil change interval and only lose small quantities between changes.

On the other hand, burning larger amounts of oil may indicate a more severe internal engine problem. Luckily, burnt oil doesn't always mean engine failure is on the way. Issues with the positive crankcase ventilation (PCV) system can also result in burned oil, and these problems are typically much cheaper and easier to fix.

To learn more, contact a service like a BMW auto repair shop.