How to Increase Car Mileage: Proven tips for better fuel efficiency

A car’s fuel efficiency is one of the most important factors that can influence a car buying decision. The Indian car buyer is primarily value-conscious, and is constantly on the lookout for ways to improve their car’s mileage. Looks, safety, features, performance — these characteristics draw potential buyers into showrooms. But a car’s mileage in the long run can result in them acquiring the vehicle..

In fact, fuel efficiency matters now more than ever - fuel prices in India are through the roof, directly affecting car owners with every kilometre travelled. Then there’s the mounting environmental concerns, with the long-term viability of petrol and diesel cars itself in question. The fact remains: fuel-guzzling vehicles just aren’t environmentally friendly. 

However, nearly every vehicle’s mileage can be improved by following a few simple tips. These tips to improve fuel efficiency range from regular vehicle maintenance to changing driving habits. Proven to improve car mileage, these tips are easy to follow and incorporate in your driving style and routine. 

Don’t forget to join the CARS24 official auto community, CLUTCH for more discussions, news updates and more. 

Factors that influence car mileage

If you have been getting lower-than-expected fuel efficiency from your car, don’t be alarmed. There are a few factors influencing your car’s mileage that are worth looking at in order to improve it. 

Impact of driving habits

As you might have guessed, one of the biggest factors influencing your car’s fuel efficiency is how you drive it. Poor driving habits — aggressive acceleration, sudden braking, overspeeding, only driving short distances, overcooling the cabin using the air conditioner — will lead to lower mileage in your car. All car engines have a sweet spot of efficiency: a range of engine speed/load at which the engine is operating at its most efficient. Bad driving habits put you outside of this range of efficiency.

Importance of regular vehicle maintenance

With all other factors remaining the same, a poorly maintained vehicle will exhibit higher fuel consumption than a well-maintained vehicle. Everything from the age and condition of engine oil, transmission oil, and air filters, to the state of the brakes and the condition of tyres can have an effect on fuel efficiency. Old engine oil, for example, cannot efficiently lubricate the moving parts in an engine that experience friction. Even tyres that aren’t at manufacturer-recommended air pressure can lead to an increase in friction between the road surface and the wheels. The thumb rule in fuel-saving tips is simple: When frictional losses go up, fuel efficiency goes down.

External factors: Traffic and road conditions

Another important factor influencing mileage is something you may think is out of your control: traffic. Driving in heavy, stop-go traffic is a sure-shot way to get lower efficiency. This is because your car spends more time idling when stuck in traffic, wasting precious fuel in keeping the engine and air conditioning running. According to the Indian Ministry of Road Transport and Highways, a car consumes around 0.15 to 0.2 litres of fuel per minute while idling. Similarly, bad roads can keep you from maintaining a smooth, constant speed, forcing you to constantly slow down for obstacles. 

ARAI vs real-world mileage 

The mileage that you see advertised for a particular car is usually achieved in controlled tests. The vehicle is operated according to a preset driving cycle, meant to replicate a range of typical driving scenarios, such as slowing down, speeding up, and stop-go traffic. But real world driving scenarios differ vastly and do not mimic the conditions simulated in these tests. . 

ARAI-certified fuel efficiency figures are an unreal representation of a car’s mileage. Real-world driving is far more chaotic. It includes variance in driving habits, vehicle condition, road conditions, traffic, and ambient temperature — factors that can greatly influence car mileage. 

Top tips to improve your car’s mileage

No matter the car you drive — old or new, petrol or diesel, manual or fuel-efficient automatic, hatchback or SUV — there are a few tips to improve your car’s mileage. If you’re experiencing poor fuel efficiency, or simply want to improve it, go through this list of car fuel efficiency tips first in addition to tweaking your driving technique to get the best results. 

Maintain optimal tyre pressure

Running your tyres at lower than recommended pressure may improve ride quality and comfort but it comes at a cost. An under-inflated tyre offers more rolling resistance, equating to more friction between the road and tyre. As we’ve established, increasing friction in any way decreases fuel efficiency. 

Manufacturer-recommended tyre pressures are usually found on the driver’s door jamb for easy reference. These figures are arrived at after extensive testing to provide the best balance of grip, ride comfort and efficiency — use them. 

Schedule regular engine maintenance

Regular maintenance is the key to ensuring you get the best fuel efficiency possible from your engine. Components like air filters can get clogged with dust and dirt, decreasing airflow to the engine and dropping efficiency in the process. Engine oils become thicker and more viscous, increasing friction in the engine. This, as we know, is the number one enemy of efficiency. Even old spark plugs will be unable to provide as strong a spark, leading to a reduction in performance and efficiency. 

Manufacturer-recommended service intervals based on Indian driving conditions are provided in your car’s user manual. In most modern cars, the instrumentation can also provide an alert when a service is due. It’s a good idea to follow these intervals as closely as possible if you seek to extract the best fuel efficiency from your car. 

Avoid rapid acceleration and hard braking

It should come as no surprise that the harder you drive your car, the worse your fuel efficiency will be. Adopting a smooth driving style instead, planning ahead for acceleration and braking, can increase your car’s fuel efficiency. Braking too hard usually means you have approached a situation with too much speed, possibly accelerating aggressively when you could have been coasting efficiently instead. There’s a fine line when it comes to efficiency though, too far on either side and you’re hurting fuel efficiency.

In fact studies have shown that accelerating at a brisk pace till the most efficient engine speed is reached is more favourable for fuel efficiency than overtly gentle acceleration. This is because your engine will spend less time at rpms where it’s less efficient. Get to that point quickly, and try to stay there, or coast where possible to reduce fuel consumption.

Reduce extra weight in the car

Ever noticed that lighter cars are usually more fuel-efficient than heavier cars? Or the drop in efficiency you notice when you’re driving with a car full of passengers, versus driving solo? The more weight your engine is trying to move, the harder it has to work. Heavier vehicles have greater inertia and more rolling resistance, both enemies of good fuel efficiency. 

Even carrying around unnecessary weight equal to one or two passengers can make a difference in fuel efficiency. According to the US EPA, every 45 kg of weight added can decrease a car’s fuel efficiency by 2 percent. So, if you use your car’s boot as an extension of your home’s storage, take this as the opportunity to remove heavy items you may not need.

Use air conditioning smartly

A vehicle’s air conditioning can decrease your fuel efficiency by as much as 25 percent in hot weather, especially on short trips, according to the EPA. It is advisable to roll your car’s windows down and rely on natural ventilation when the weather allows, especially on trips shorter than a few kilometres. On the flip side, using your car’s AC is better for fuel efficiency at speeds over 90 kmph as open windows create more drag, decreasing efficiency. 

Using your car’s climate control at the lowest setting is also bad for fuel efficiency as it puts more strain on the engine. Adjust the temperature to a medium temperature and use a higher blower speed to maximise cooling. 

Fuel-efficient driving techniques

Changing your driving habits has the largest effect on fuel efficiency, but is also usually the hardest to implement. The good news is that once you’re aware of what exactly in your driving style is hurting your car’s mileage, you can work on addressing those aspects one at a time. Before you know it, you’ll be planning your trips ahead of time, anticipating traffic and driving smoother than you ever have before. It’ll make for better fuel efficiency and a smoother drive for passengers. 

Maintain consistent speed

Acceleration uses more fuel than maintaining a constant speed under most circumstances. So, instead of speeding up and slowing down repeatedly, try and maintain a consistent speed that’s suitable for your road and traffic conditions, in accordance with local speed limits. Finding the most efficient speed is a factor of the right engine speed in the right gear.

Shift gears at the right time

In continuation of the previous point, shifting gears at the right time also ensures your engine is operating at the optimal rpms. At the same time, care should be taken to not overload the engine by running it at very low rpms in higher gears. Lugging the engine puts undue stress on it and reduces fuel efficiency, contrary to popular belief that it’s a fuel-saving measure. At the same time, over-revving an engine also uses more fuel. In stop-go traffic, it may be advisable to use a single gear that allows you to pull away cleanly from a standstill, while still allowing you to manage traffic without jerks. 

Plan ahead to avoid stop-and-go traffic

The only way to efficiently reduce time spent in traffic is to plan your journeys. Avoid peak traffic hours for travel as much as possible. UtiliseGPS apps to look up alternate routes to destinations; a longer route that’s free of traffic could actually help save you fuel. 

Common mistakes that lead to poor mileage

Let’s face it, we’re all guilty of making one of these common mistakes that lead to poor mileage. Whether by accident or design, sometimes it’s just impossible to follow every golden rule when it comes to improving fuel efficiency. That said, these are small but significant car fuel efficiency tips to watch out for in your quest for better mileage. 

Overusing air conditioning

It's a natural tendency to turn your car’s air conditioning to its lowest setting on a hot day. But as you may be aware by now, this has a significant negative effect on mileage. Instead one can use a medium temperature setting but a higher blower speed to achieve similar results over a slightly longer period. 

You can also use a reflective windscreen shade to reduce the amount of heat soak your car experiences when parked. This itself will reduce the peak temperature inside the car when parked, needing less cooling to get to a comfortable level. Another tip is to quickly open and close the doors a few times before starting your journey to circulate the hot air out of the car. Once on the move, run the air conditioning at a medium setting with the windows half open to let the cool air replace the warm air. 

Ignoring scheduled maintenance

An improperly maintained car won’t be running at the efficiency it was engineered to. Components like air filters, oil filters and engine oils are engineered to last a certain number of kilometres before they start to have a negative effect in efficiency and performance. 

Again, manufacturer-recommended service intervals are designed to keep every aspect of your car’s performance close to peak, even as the car ages. As kilometres rack up, it becomes even more important to change critical components like air/oil filters, engine oil, spark plugs and more. These components should be replaced periodically,  according to the recommended schedule provided by the manufacturer, to avoid losing performance and fuel efficiency.

Carrying unnecessary weight

Ideally, your car’s boot should only permanently be carrying your spare tyre, jack and other emergency kit essentials. A few spare shopping bags, or a gym bag with spare clothes won’t make any difference to your fuel efficiency weight-wise. On the other hand, if you find yourself lugging around furniture items, or other heavy objects, or tools simply because you have no better place to put them, you’re losing fuel efficiency that can be easily avoided. 

Tools and technology for better mileage

Now that we’ve covered the universal fuel saving tips, there are a few more things to help you get the most kilometres per litre. As they say, knowledge is power — you can only know how to fix something when you can identify the issue. Technology can give you a free leg up in diagnosing poor fuel efficiency, either through third-party apps, or your car’s own mileage tracking analytics, if present. 

Mileage tracking apps

A mileage tracking app helps you keep track of fuel efficiency over a period of time, enabling you identify low and high-efficiency periods. This is helpful in keeping track of any changes in driving habits, or traffic/road conditions. A mileage tracking app is like a virtual logbook, usually allowing you to keep track of distance travelled before refills, the average cost per refill, and more. The ability to add notes to each refill is useful if you’re trying out different fuels from different vendors, additives or driving techniques. 

Benefits of using eco-driving modes

Many modern cars offer eco-drive modes which alter climate control settings, throttle mapping, or even engine mapping, to help extract better fuel efficiency. On cars where the throttle mapping or engine mapping is changed, you can expect lower performance but better efficiency. As a plus point, many cars also offer onboard fuel efficiency analytics to help you keep track of your driving in real time. Some cars also gamify your driving with scores for acceleration, braking and fuel efficiency, which go a long way in helping you stick to better driving habits. 

Long-term strategies for sustaining high mileage

Once you’ve tasted the sweet success of improving your car’s mileage, it’s only natural to want to try and replicate it on a daily basis. This does mean following the steps to better fuel efficiency regularly, to make them your own long-term strategies for fuel efficient driving. 

Regular car inspections

From dirty air filters, to sticky brakes, anything can happen to reduce your car’s efficiency during regular use. The best way to avoid this is to send your car in for regular inspections. At scheduled services, leave a note for the service centre to also inspect your brakes and brake pads for any wear that’s out of the ordinary. If you have noticed a drop in fuel efficiency, inform the service centre of the same, and carry out the recommended corrective action. That said, it is natural for a car’s fuel efficiency to drop a little as it ages, so don’t get too alarmed when it does, unless the change is too drastic. 

Route planning to avoid traffic

Planning your route to avoid traffic will save you fuel in the long run. Not just that, it’ll also save you time and the stress of being stuck in traffic. A quick glance at a maps app will show you the areas of high traffic congestion and offer you alternate routes to avoid it. It’s definitely worth making this tip part of your pre-journey routine. 

Opting for high-quality fuel

Better fuels may come at a premium cost over regular fuel, but will usually help your car perform more efficiently. Many high-quality fuels have higher octane ratings and additives that help increase a car’s performance and efficiency. As a happy bonus, high-quality fuel will also lead to less sediments in your fuel filter, which will ensure optimal fuel flow rates for longer periods of time. 

Conclusion

This collection of eco-friendly driving tips is meant as a pointer in the right direction when it comes to extracting the best from your car. Ideally, follow all the tips for the best results but since mileage is also dependent on factors not in your control, don’t be worried if you can’t always follow them all of the time. 

FAQs

Q. How to improve fuel efficiency in a car?

You can improve fuel efficiency in a car by avoiding hard acceleration and braking, and heavy traffic routes.

Q. How can I increase the mileage of my car?

You can increase the mileage of your car by maintaining consistent speeds and planning ahead. Regular maintenance of your car also helps.

Q. What can I add to petrol to increase mileage?

Several brands make additives that you can add to petrol to increase mileage. These additives enhance the pertol’s properties and enable better combustion, leading to reduced fuel consumption. But these should be used once you are already following all the other best practices. 

Q. What is the best rpm for fuel economy?

In normal conditions, the most efficient rpm range in a petrol car is between 2000 and 2500 rpm

Q. Why is my car mileage so low?

One of the reasons why your car mileage is so low could be related to poor maintenance or some other mechanical issue. If you feel your mileage is lower than it should be or has been, get it checked by a professional. 

Q. Which gear gives the best mileage in a car?

This totally depends on the driving conditions. If you mostly drive in the city, keeping in the gear that avoids lugging, while also keeping the rpm low, will give the best results. On the highways, where traffic is less and the car can be driven consistently at higher speeds, keeping it in top gear will maximise fuel efficiency.