6 Reasons Your Vehicle Is Burning Oil

If your vehicle is burning oil, you'll need to investigate to determine the cause. Oil serves several purposes in combustion engines. It lubricates the internal components, removes debris and regulates the temperature. Without oil -- or with low levels of oil -- your vehicle's engine may sustain catastrophic damage. Here are six possible reasons your vehicle is burning oil.

#1) Worn Piston Rings

One of the most common reasons vehicles burn oil is worn piston rings. Piston rings are mechanical seals that, as the name suggests, sit around the pistons. They typically consist of O-rings that form a barrier between the pistons and the cylinder walls. Over time, piston rings can wear out, resulting in oil leaking into the combustion chamber where it's burned with gas and air.

#2) Wrong Oil Type

Using the wrong type of oil may result in increased oil consumption. Not all varieties of oil are the same. Some of them are thicker and less viscous than others. High-viscosity oils such as this are less likely to leak past piston rings and other seals. Regardless, you should only use the type of oil recommended by your vehicle's automaker.

#3) Engine Overheating

Allowing your vehicle's engine to overheat may result in it burning oil. Normally, the coolant and radiator will keep your vehicle's engine temperature in check. But problems can arise that allow the engine temperature to increase beyond "normal" levels. If the engine overheats, it may burn oil.

#4) PCV System Failure

Failure of your vehicle's Positive Crankcase Ventilation (PCV) system can lead to increased oil consumption. The PCV valve, for instance, may become clogged. A clogged PCV valve will result in pressure building up within the crankcase. All of this pressure can force oil past the seals where it's burned in the combustion chamber with gas and air.

#5) Blown Head Gasket

A blown head gasket is a common cause of oil consumption. Head gaskets are large seals that sit between the engine block and the cylinder head. It contains many different passages, including passages for oil, coolant and combustion gases. If your vehicle's head gasket fails, these fluids and gases may mix together. The oil may leak into the combustion chamber, which will cause your vehicle to burn oil.

#6) Old Age

How old is your vehicle? Many drivers are surprised to learn that it's normal for older vehicles to burn at least some oil. If your vehicle has surpassed the 10-year mark, it will probably burn some oil. What's not normal, however, is excessive oil consumption. Even if your vehicle is older than a decade, it shouldn't consume or otherwise burn a lot of oil. Excessive oil consumption is typically a sign of an underlying problem, such as worn piston rings or the wrong type of oil.