Does a Cold Air Intake Increase MPG?

Improving fuel efficiency is important for everyone, especially in these times of high and rising gas prices. While getting the most out of every dollar and gallon is the top priority for most drivers, fuel efficiency also contributes to a better environment, which is good for everyone! So you might wonder what you can do to increase MPG?

Well, there are many things you can do to improve your car’s MPG. One option that many consider is installing an aftermarket cold air intake. But does a cold air intake increase MPG?

Cold air intakes can improve fuel efficiency by 3-5 MPG. With a cold air intake, the engine gets a lot cooler and denser air, which allows the engine to combust the fuel more completely and efficiently, resulting in increased MPG.

Follow along to find out how the cold air intake system work and why cooler air can improve your car’s fuel efficiency. Let’s dig into it!

What Determines Engine Fuel Efficiency?

One of the main things determining engine fuel efficiency is the air-to-fuel ratio. This is the amount of air that enters the engine for every unit of fuel.

The ideal air to fuel ratio is 14.7 to one for every engine to achieve optimal efficiency. This is known as the stoichiometric mixture and means that for every 1 gram of fuel, 14.7 grams of air are required.

This means if the ratio mixture is greater (lean mixture) or less (rich mixture), this causes a negative impact on your miles per gallon efficiency.

How Does a Cold Air Intake Work?

A cold air intake system works by sucking in air from outside of the engine bay. It means you move the air filter so that cooler, more dense air can be sucked in instead of warmer air from the engine.

This is why cold air intakes are often placed in the front bumper or near the grille. By moving the air filter outside, you ensure that cooler, denser air is entering the engine, which will result in increased MPG.

Does a Cold Air Intake Increase MPG?

Studies have shown that air intake temperature is one of the alternative strategies to improve fuel consumption and reduce exhaust emissions. This is due to the cold air is denser and contains higher oxygen availability.

A higher concentration of oxygen at a lower air intake temperature leads to a more complete mixing process and more complete combustion of the fuel. It means your engine will perform better.

Therefore, installing a cold air intake will likely result in increased miles per gallon.

Related: Do Cold Air Intakes Increase Horsepower?

Can a Cold Air Intake Decrease MPG?

In some cases, a cold air intake can decrease MPG. Moving the air filter outside can allow water to get into the engine if not properly installed.

If water does enter the engine, it can cause serious problems, resulting in decreased efficiency and reduced MPG. If you already did, or planing to install a cold air intake on your car, make sure to protect your filter with a hydroshield.

Here is a great Youtube video from milanmastracci on how to protect your car from hydrolocking. Make sure to also check out his video on how to install a cold air intake.

High Flow/Performance Air Filter vs. Cold Air Intake for Increased MPG

You might wonder if there is any difference between a high-flow/performance air filter and a cold air intake when it comes to increasing MPG. The answer is yes!

A cold air intake will provide a greater increase in MPG than a high flow air filter because it allows for cooler, denser air to enter the engine while a high flow air filter does not.

A high-flow air filter’s biggest purpose is to allow more air into the engine, but it does not necessarily mean that cooler air is entering. However, the high flow/performance air filter does increase horsepower, resulting in a small MPG increase.

What Other Benefits Does a Cold Air Intake Have?

In addition to increased miles per gallon, a cold air intake can also provide other benefits. These benefits include:

Efficient and Reusable Filter

A benefit of cold air intake is that it provides an efficient and reusable filter. Not only will it keep dust, dirt, debris, and other particles away from your engine, the filter doesn’t need to be replaced continually, unlike most other types of filters.

Increased Horsepower

Another great benefit of cold air intake is that it increases horsepower. As mentioned before, for an engine to achieve optimal efficiency, the ideal air to fuel ratio is 14.7 to one. By achieving this, you can expect to see a significant difference in performance.

In fact, many experts say it can result in up to 20% more power, depending on the vehicle’s make and model. That’s insane, isn’t it?

Although it may sound too good to be true, proper combustion can in some cases yield results hard to believe.

However, keep in mind that a cold air intake is no guarantee your vehicle’s performance will significantly increase. It varies from car to car and some people might not even notice any difference at all.

Changed Engine Sound

With increased airflow, you may notice a louder and deeper noise from the engine. However, some say it might actually do the opposite. So does a cold air intake really make your car louder?

Is It Legal to Install a Cold Air Intake System?

This is a great question and the answer may surprise you. In most cases, yes, it is legal to install a cold air intake system on your vehicle.

However, in California, it is illegal to modify or adding any aftermarket part, including the air intake system of a vehicle as it is considered to be tampering with a smog-controlled engine.

Therefore, by installing a cold air intake, you could be breaking California law, unless the cold air intake has received CARB-issued exemption.

Downsides With Stock Intake Systems

A stock intake system is the air intake system that comes with your vehicle when you purchase it. It’s designed to work well enough for the average driver but isn’t necessarily designed for optimal performance.

One of the main downsides of stock intake systems is that they can often be restrictive. This is because they are designed to meet the minimum needs of the average driver and not necessarily for those who want to get the most out of their vehicle.

That is why you can expect to see increased MPG with an aftermarket upgrade.

Is It Worth Installing a Cold Air Intake System For Improved Fuel Efficiency?

As we have learned by now, a cold air intake can improve fuel efficiency. Not only will you see an increase in MPG, but you’ll also see an increase in horsepower and acceleration.

So if you’re someone who is looking to get the most out of your vehicle in terms of performance and fuel efficiency, then a cold air intake system is definitely worth the investment.

Keep in mind that the results may vary from car to car and also from other car owners’ experiences. There is no guarantee you will notice any difference at all.

Best Cold Air Intakes Brands on the market

When looking for this kind of aftermarket upgrade, quality cold air intakes from reputable manufacturers with proven results are essential for the best performance.

Here are some of the best cold air intake brands on the market, and they should definitely be at the top of your consideration list if you are looking to buy an aftermarket upgrade for your vehicle.

  • K&N Intakes
  • Spectre Performance
  • Injen
  • AEM
  • Volant
  • Airaid


To sum it all up, does a cold air intake increase MPG? Yes, it is possible to see an improvement in fuel efficiency with a cold air intake system, up to 3-5 MPG. The cold air intake lowers the temperature of the air coming into the engine, which results in more complete and efficient combustion.

While it may not be a night and day difference for all car owners, if you’re looking to get the most out of your vehicle’s potential performance and fuel efficiency, it’s could be worth the investment. Just be sure to get a quality product from a reputable manufacturer for the best results.

Happy driving!​

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Rickard Cefalk

Rickard is the owner of and a dedicated and avid do-it-yourselfer who has always enjoyed working on his own vehicles since childhood. He now devotes his time to sharing his expert knowledge of car maintenance and other car-related information through his website.

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