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Can Spark Plugs Affect Gas Mileage?

Gasoline car spark plug replacement.

Spark plugs gone bad can affect our gas mileage in a major way. Damaged spark plugs can reduce gas mileage by up to nearly 30 percent, according to the National Institute of Automotive Services. This drives home the fact that we need to pay close attention to our spark plugs by getting our vehicles serviced often.

Ensure that we buy the correct ones, and replace the old ones on a timely basis. Many other problems can occur when we use worn spark plugs, including engine damage. Let’s fire up on all cylinders as we look into the importance of spark plugs and how they affect our fuel economy. 

Can Spark Plugs Affect Gas Mileage?Bosch Automotive (9608) OE Fine Wire Double Iridium Spark Plug - Pack of 4

A spark plug lights the explosive atmosphere in each cylinder independently. Even if a single spark plug dies, the engine need not completely die. However, you will experience decreased acceleration and engine power, which will cause you to use more gas than necessary and lower your MPG.

Spark plugs are subjected to extreme heat and pressure inside the engine, which causes them to wear out over time. Similarly, poor MPG is a result of worn spark plugs, which cause the spark plug spaces to increase. That is because a higher voltage is needed to create a curve between the electrodes if a spark plug space is larger.

The more efficient the combustion, the less energy and power the engine needs. This is why regular car maintenance and high-quality spark plugs are essential.

Can New Spark Plugs Increase Fuel Economy?

Full electric vehicle dashboard showing speedometer, odometer, and battery range.

Changing an antiquated spark plug for a modern one can improve gas mileage by as much as 3 percent. This might not appear to be much, but it can add up to significant savings over one year, two years, or the lifespan of the vehicle.

If So, Then How Does It Operate?Denso IT16TT Iridium TT Spark Plugs 4713-4 PK

The ignition spark in a standard spark plug is created by two flat-surfaced electrodes in a very small space, lowering the likelihood of combustion. On the other hand, the Iridium Twin Tip Spark Plugs include two needle-thin electrodes that promote the flame’s growth in all three dimensions, rather than just two. This innovative structure allows the flame to spread more rapidly and efficiently, leading to more robust combustion.

The improved performance of the engine is attributed to its ignitability. Reportedly, the makers have conducted comprehensive trials, lab-testing the fuel usage of a car engine employing different spark plugs, either of their design or those of rivals. The findings demonstrate unequivocally that an engine performs better when given more room for the igniting flame to expand.

The Iridium TT spark plug, for instance, has been demonstrated to cut CO2 emissions and fuel consumption by upwards of about 3.4% with a full load.

Ask Your Garage Operators for Efficient Spark Plugs

The Iridium spark plug not only increases fuel economy but also extends the life of the engine your customer uses. Iridium TT spark plugs have a lifespan of 120,000 kilometers, or three times that of conventional spark plugs’ 40,000 kilometers. Iridium TT’s superior spark plug design and one-of-a-kind iridium rhodium alloy boost engine output and overall vehicle efficiency.

The enhanced performance is cited by several experts as the reason they recommend Denso spark plugs.

Save Gas and Help the Planet By Swapping out Your Spark Plugs

By maintaining your vehicle and replacing the spark plugs as needed, you may increase your gas mileage and decrease your expenses without negatively impacting the environment. If spark plugs are in good shape, automobiles can reduce their emissions. Mismatched spark plugs can have a dramatic effect on fuel economy and can severely damage an engine.

When an engine has trouble starting and wastes a lot of gasoline trying to get going, carbon deposits form around the spark plugs.

Spark Plugs Uses

Technician checks an old spark plug coil that has burn scars.

An engine is an intriguing machine, especially considering its use of fuel as its primary energy source. I’m curious, nonetheless, as to how it manages this miracle. The hypothesis of internal combustion explains.

The potential energy inside the fuel we put into our vehicle engine is released during the combustion process as heat, which drives the wheels. The engine process makes it possible to carry out the aforementioned steps. As part of the engine’s combustion cycle, the valves open to let a flood of explosive air and fuel into the cylinder.

By raising the piston in your engine, you can reduce the volume of the fuel-air combination to a negligible fraction of its original size, hence boosting the mixture’s potential energy. At the peak of tension, a small spark burns the fuel/air combo, resulting in a blast that draws the pistons back down as well as rotates the crankshaft, creating the power that drives your car forward. The explosion that propels the pistons in an internal combustion engine is ignited by a spark from the spark plugs.

These simple plugs work because an electrical arc is created between two leads that aren’t in direct contact with one another but are close enough for power to “leap the gap” between them. Spark plugs and associated electrical plus timing parts make up the ignition system.

Iridium Spark Plugs Benefits

As opposed to copper and platinum, iridium spark plugs provide a seemingly limitless list of benefits. It’s difficult to pick the top benefits when there are so many that surpass the competition. Here are some of the most obvious advantages of iridium spark plugs:

Raise Efficiency of Fuel Use

The increased ignition profile guarantees complete combustion of the fuel you use. Using iridium spark plugs will result in somewhat better fuel economy, but the difference won’t blow your mind. Iridium spark plugs help save money and the environment by maximizing the efficiency with which gasoline is used.

Boosts Velocity

Using iridium spark plugs can make a noticeable difference in the speed at which a gasoline-powered vehicle accelerates. This enhancement is a direct outcome of how quickly gasoline engines learn to respond to the throttle movement generated by iridium spark plugs. Vehicles that need to achieve highway speeds in a short amount of time can benefit greatly from the higher acceleration speeds.

Boost the Engine’s Power

Increased engine output is possible with iridium spark plugs due to their long lifespan. Because of this, they are a viable spark plug choice for off-road vehicles and towing vehicles that could benefit from a bit of extra power.

Cleaner Engine Ignition

A clean engine start is guaranteed whenever iridium spark plugs are used. Due to improved combustion, there is less dispersion at the location of the spark, resulting in a cleaner engine start.

Extremely Long-Lasting

When compared to platinum spark plugs, iridium ones are eight times more durable. Plus, their hardness is six times that of steel, and their melting point is 700 degrees hotter. They can last about 25% longer than platinum spark plugs, making them one of the longest-lasting alternatives.

Iridium Spark Plugs’ Drawbacks

Iridium Spark Plugs on a white background.

Although the benefits of iridium spark plugs much exceed the drawbacks, they should nevertheless be carefully considered before implementation. Iridium spark plugs have these major drawbacks.


One major drawback of iridium spark plugs is their high price tag. Iridium-based spark plugs cost more than their competitors because they last significantly longer. The high price of iridium is justified by the fact that no other material comes close to matching its performance.

Brittleness of Coating

Iridium is a strong material that greatly enhances the performance of spark plugs, but it can become fragile if it is not properly applied. When installing spark plugs, care must be taken to avoid bumping or scratching the electrodes, which can cause the plug to become brittle and reduce its effectiveness.

Combustible Particles

When working with iridium spark plugs, it’s important to avoid damaging the plug by scraping it against other engine parts. At high enough temperatures, the resulting dust can catch fire due to oxygen erosion plus fluorine pollution.

What is a Spark Plug Made From?

Spark plugs on black background.

Spark plugs are often made from durable elements that can withstand millions of blasts before wearing them out or needing to be replaced. However, your engine’s performance will inevitably decline as a result of explosions and corrosion, which can also lead to other issues including misfiring and complete inability to fire.

How Often Should I Have My Spark Plugs Replaced?

The “extended-life” spark plugs used in modern cars are installed by default. Customers are raving about better sound quality for the same price or less than a standard plug. Extended-life spark plugs typically have a lifespan of roughly 100,000 miles, according to the manufacturer.

These plugs lose efficiency and are more prone to misfire as they near the close of their service life due to a gap that forms between the two leads. If your vehicle’s spark plugs have deteriorated to the point where they break, you may need to replace the cylinder walls, which is an extremely expensive repair. The instruction manual for our vehicle should indicate the length of time the spark plugs should last.

Never put more miles on a pair of spark plugs than the manufacturer recommends.

Guidelines for Buying Replacement Spark Plugs

Get replacement spark plugs that are suited for your specific vehicle. You may find help with this at most auto parts stores, and they stock parts for a large variety of vehicle models. Though platinum and iridium-made items cost several times as much as copper ones, they last considerably longer.