Why is My Car Burning Oil?

Seeing a puddle of oil under your vehicle is frustrating, but noticing a loss of oil without a visible leak can be even worse. When the leak is external, it’s a lot easier (and generally less expensive) to get diagnosed.  When your motor is burning oil, either internally or externally, it can sometimes be much more difficult to find the 

Everybody knows how vital oil is for your vehicle, as it’s the lubricant that allows all the moving metal components with tight tolerances to operate smoothly. Oil is also important for the cooling of your motor and transmission, as the fluid can draw heat away from metal parts. 

What Does Burning Oil Mean?

When a vehicle is burning oil, it means that the oiling system is losing oil over time. The escaped oil is entering the combustion chamber and igniting with the air and fuel mixture and passing through the exhaust. . 

Burning oil can take place in two different ways, externally or internally.

Internal leaks can often signal a major problem within your motor. This happens when there’s a failed seal within the engine that allows oil to leak into the combustion chamber and is subsequently ignited and burned off with the rest of the fuel. Worn valve seals, piston rings, or other internal failures are often to blame for this.

If you notice the smell of burning oil from your exhaust, a loss of oil, and/or black smoke emanating from the tailpipe, you should avoid driving the vehicle any further and have it inspected by a trusted professional who can pinpoint your issue.

What Causes Burning Oil?

Head Gasket Leak

One of the most dreaded issues an engine can have, a head gasket leak, refers to when oil is able to enter the combustion chamber through a rip or hole in the head gasket and burn up.

Head gasket failures can cause serious issues such as overheating, misfires, and eventually engine failure. 

head gasket sitting on engine block
Lewis Collard, Attribution, via Wikimedia Commons

Leaking Turbo Seals

In turbocharged vehicles, turbo seals are a common culprit of oil burning. When these seals fail, oil is able to make its way into the engine r and will be burned. Depending on the location of the leak, this can cause oil to either be pushed into the engine from the intake side of the turbo, while on the other side, oil will be pushed into the hot exhaust system and subsequently burned.  

Damaged Valve Seals

Your valve seals keep oil out of the combustion chamber, but as they degrade and fail over time, oil can be introduced into the cylinder and cause the internal burning of oil. 

Damaged Piston Rings

Similar to valve seals, piston rings are also vital for keeping oil from entering the wrong portions of your engine and causing oil to be burned, along with various other issues as a result.

External Oil Leak Causing a Burning Smell

External leaks happen when oil is leaking to the outside of the engine. This often causes dripping onto hot engine components and the oil is burned off, causing a recognizable burning oil smell. Often external leaks are less serious, but can still cause oil starvation and other problems if left unresolved.  

Incorrectly Installed or Damaged Oil Filter 

Your vehicle’s oil filter keeps your oiling system loop and motor free of debris. However, when this part is either damaged or not installed properly, it can leak oil from around the edges, often right onto the hot engine block or other components. 

Luckily, this issue can be easily remedied, as oil filters are generally cheap and easy to install. 

Removing oil filter with a tool
Dvortygirl, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons

My Car is Burning Oil! What Should I Do?

If you’re experiencing any loss of oil, internal or otherwise, you should avoid driving the vehicle and have it inspected and repaired by a trusted professional. Running without the proper level of oil can cause irreversible engine damage, overheating, and various catastrophic failures of certain components. 

Oil Burning Diagnostics and Service in Naperville, Illinois

The ASE-certified technicians at Becker Service Center in Naperville are your premier destination for oil changes, service, and diagnostics. Call or schedule online with us today!