Why Oil Smells Like Gas (Causes & Solutions)

If you notice that your car’s oil smells like gas, there might be a problem.

When you check your oil and the dipstick smells like gas, don’t waste time trying to figure out where the gas smell is coming from.

Knowing what the problem is might help you decide whether immediate repairs are needed or if you can wait a bit before doing any work yourself or seeking help from a mechanic.

This article provides you with the common reasons your car’s oil smell like gas and how to fix this issue.

Let’s get started!

6 Common Reasons Your Oil Smells Like Gas

Reasons Your Oil Smells Like Gas

Several factors can be why your car’s oil smells like gas. Some of them include:

1. Frequent Short Distance Travel

The current OBD-II cars are designed to operate richly during startup, but the fuel/air ratio becomes smaller as the operating temperature increases. This prevents poor performance and stalling because enough fuel is distributed in cold operations.

Meanwhile, if you eventually take long-distance journeys, the excess fuel may, in turn, dilute the oil.

2. Faulty Injectors

Atomization results in the complete burning of fuel in the injector under perfect conditions.

However, when the injectors get a bit older, it loses their ability to atomize fuel efficiently, and this causes the fuel to burn incompletely.

As a result, insufficient burnt fuel mixes with lubricating oil from the engine when it travels through the piston rings causing the oil to smell like gas.

3. Rich Air/Fuel Ratio

When some sensors are bad, the engine control module can be tricked into releasing too much fuel for a particular task.

This eventually leads to what is known as ‘rich condition’; this does not enable all the injected fuel in the engine to burn totally.

As a result, excess fuel washes past the cylinder rings and mixes with the oil in the engine. This is another reason why a car’s oil smell like gas.

4. Problems With the Ignition System

Different components in the ignition system of an engine work hand in hand to make sure the fuel that goes into the engine’s cylinder gets ignited.

When one of the components, such as the spark plugs, gets faulty or fails, the fuel might not burn totally in some cylinders.

In more severe cases, the fuel that washes past the piston’s rings in the cylinder gets mixed up with the oil in the oil pump.

5. Infrequent Oil Changes

Most times, a small quantity of fuel goes into the engine’s lubricating oil even when there is no mechanical problem. However, the fuel is primarily tiny and does not affect the engine’s lifespan.

Dilution of fuel that produces a gas-like smell is mainly caused by irregular servicing, making the fuel mix with the oil.

6. Engine Wear

The internal wearing of an engine may lead to gasoline and oil mixture in some cases. Proper combustion will be hindered once piston rings or walls of the engine’s cylinder start excess wearing.

The engine gets at risk when there is wear on the accelerated bearing due to incomplete burning of a larger quantity of fuel which washes down the walls of the engine’s cylinder.

Also Read: Oil on Spark Plug Threads (Causes & Solutions)

How Does a Gasoline Engine Work?

How Does a Gasoline Engine Work

Vehicles whose engine uses gas as fuel has lots of cylinders. There are various cylinder numbers in different vehicles with various engines.

For example, there may be up to 8 cylinders in a brand new Chevy Tahoe, while BMW M4 may have a 6-cylinder motor.

When searching for why your car’s oil smells like gas, cylinder numbers are insignificant. But understanding the principles of internal combustion of a vehicle that uses gas will help.

Then, the source that enables the gas to enter the oil can be easily traced.

Air intake and fuel systems supply air and gasoline that mix up in each engine’s cylinder. The two get ignited with a spark that leads to combustion, and the cylinder’s piston is driven.

The up and down movement of the piston becomes faster when there is more air, spark, and fuel.

The energy that powers the vehicle’s wheels, causing acceleration, is created from the combustion reaction.

Because of the fast circular motion of the piston, a ring surrounds each piston to contain byproducts of combustion, fuel, and air and keep them from affecting other engine components.

The multiple rotations of the vehicle’s piston make it experience high frictions and temperatures. Lubricating flexible parts and cylinders with oil prevent friction-induced overheating and free movement.

This video on Formula 1 racing car with a Cosworth engine gives an insight into how hot it can get. The vehicle’s exhaust pipe gets red hot!.

The engine’s efficiency can lower, leading to subsequent failure when things are not done correctly, and the gas gets inside the oil. Constant checking and smelling can help identify an issue quickly before any breakdown.

What Are the Symptoms of a Rich Oil-Gas Mixture?

Oil Smells Like Gas

When there are issues with a car, a few indicators help draw our attention to the problems. The same thing happens when gasoline mixes up with the vehicle’s oil; here are some symptoms of a rice gas-oil mixture.

1. Dipstick Gas Smell

A gas smell can also be detected through the dipstick during an oil level check. You will know fuel entered the oil pan when you perceive gas on the dipstick.

You can also examine how the oil falls from the dipstick. Falling faster indicates a mixture of oil and gas.

2. Strong Gas Smell

If you perceive a strong gas smell, it’s a sign that there is gas in the vehicle’s oil. Gas can be perceived strongly when much fuel goes into the crankcase.

The smell gets so intense that you can smell it when driving. The smell can even be perceived without checking the motor oil.

3. White Exhaust Smoke

The first sign of any combustion chamber issues is usually white smoke from the exhaust pipes.

There are possibilities of fuel that was not completely burnt going into the crankcase due to the richness of the fuel.

4. High Oil Level

There should be no increase in the vehicle’s oil level. The subsequent increase in the volume of oil means some other fluid goes into the oil storage.

Possible fluids that can enter the pan may be water from cylinder heads that got burnt or large amounts of gas. The color of the oil will help determine if water led to the increase or not.

What Will Happen if Oil Gets Into the Crankcase?

The oil and gas mixture has no immediate effects. But if excess gas goes into the crankcase or a small quantity of gas remains inside it for a more extended period, it may lead to some issues that may be of concern.

Here are some of them.

1. It will affect Oil Viscosity

Oil has a higher viscosity than fuel; hence it’s more suited for lubricating purposes than gasoline.

However, the oil loses its viscosity when a little gas finds its way to the oil tank and remains for a more extended period or when excess gas goes inside the oil pan.

2. Fast Wear and Tear

Wearing of the internal components of an engine occurs faster when the lubricating ability and viscosity of oil are lost.

The viscous property of oil helps prevent the wearing of internal components of an engine. However, the engine components will deteriorate faster when this viscosity is lost.

3. The Engine Could Overheat

The oil will not be able to cool down fast enough if its viscosity and lubricating ability of the oil is lost due to the presence of gas in the oil.

Excessive heating on the engine may prevent acceleration. It may also lead to severe damage to the engine components.

4. Gas Loss and Reduced Fuel Economy

A large quantity of fuel will be lost if much fuel goes into the crankcase. This leads to less capacity from the engine and fuel economy reduction.

Is It Safe to Drive if Your Oil Smells Like Gas?

Is It Safe to Drive if Your Oil Smells Like Gas

It is not advised to drive a car that the engine’s oil smells like gas. This is because if you go ahead and drive, it may harm the engine.

In addition, when gas is mixed with oil, the gas can thin oil, which reduces the oil’s viscous property. This may lead to an increase in the wearing of essential components like the engine’s bearings.

This does not imply that there will be instant damage to the engine when you drive with diluted oil. But it only presents certain risks which tend to cause harm.

This harm may not appear immediately. Therefore, it is advised not to drive a car when the oil smells like gas.

Several measures should be observed if you must drive the affected car. First, the oil and the engine’s oil filter should be replaced. This will help in the analysis of the oil sample.

The main cause of oil dilution problems must be identified and sorted accordingly immediately it is noticed. In this way, further complications can be avoided.

You can visit your mechanic immediately if you don’t feel so comfortable doing it yourself.

How to Fix Oil Smell Like Gas?

Manufacturers of engines and the manufacturers of motor oil know about oil dilution. So the oil has been produced to supply enough protection when it gets diluted to the point of regular operation.

Frequent long-distance drives on highways with small burning to maintain minimal temperature operation are advised to help manage the engine’s oil dilution.

This will bring good results. The oil will be purified due to the burning, and there will be evaporation of extra fuel inside the crankcase.

It is also more like excess heat burning. You can also choose to change the oil always if you engage more in short-distance drives.

You will understand that a not-so-friendly environment is not appropriate for the oil if you place much importance on the engine’s life span.

You will be causing damage to the engine if you treat the oil in the crankcase harshly by cold-starting, driving like 10 minutes to a station, and returning after 10 hours. There will be a need for frequent oil changes if you do this.

PS: Most vehicle manufacturers’ advise a frequent change of vehicle oil when the operating environment becomes harsh.

There is no regular information on short-distance driving, creating a harsh operating environment on your vehicle.

Carry out frequent checks on the car’s oil level. When the oil gets above the fixed point, do well to seek advice from a professional.

Also Read: How Much Oil Does My Car Need?

Conclusion – Oil Smells Like Gas

When your notice that your car’s oil smells like gas, don’t get disturbed immediately. Other possible signs accompany the smell of gas if the engine has any significant problem.

This means that the smell of gas alone may not be the first or last signal of a pending engine failure. But it should be a cause of concern if it repeatedly happens with every oil change.

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