How Can I Improve Gas Mileage In My Nissan Altima?

By Nick Marchenko, PhD

Updated: September 12, 2023

Why might you be concerned about your Nissan Altima's fuel efficiency? Even with the rise of hybrids and electrics, many motorists are still fond of the trusty gasoline-powered Nissan Altima. Their affinity for this classic stems from its straightforwardness and ease-of-use compared to its hybrid and electric peers.

Yet, it's an almost universal experience – at some point or another, every driver has wondered how they might extend their Altima's miles per gallon (mpg). Factors like weather conditions and the vehicle's health can influence fuel consumption significantly.

The primary reasons to optimise fuel consumption in the Nissan Altima are: to cover more ground on a single tank, save a bit of money, and just, well, drive further.

This piece will delve into the main culprits behind excessive fuel use and suggest some crafty ways to be a bit more frugal at the pump.

Key Takeaways:

• Diesel engines, in general, guzzle about 20-30% less than their petrol counterparts, thanks to the denser and more efficient nature of diesel.
• For top-notch fuel efficiency in the Nissan Altima, try to stick to the recommended cruising speeds, make friends with the cruise control, and engage that ECO-Mode.
• A well-maintained Nissan Altima, especially where spark plugs, filters, oil, and other engine components are concerned, can vastly reduce its thirst for fuel.
• Modern Altimas, laden with all sorts of sensors, can alert drivers to any issues that might be causing a bit of a drinking problem (fuel-wise, of course).

Which Nissan Altima model boasts the most impressive mpg?

Several variables play into the fuel efficiency of the Altima. Engine structure, cylinder count, and valve number, for instance. There's a notion out there that a larger engine inherently means higher fuel consumption. That's not quite the full story.

Engines on the smaller side (around 1 to 1.2 liters) have fewer cylinders and sip fuel more sparingly with each stroke, leading to rather attractive fuel economy figures.

In a delightful twist, some beefier engines also surprise with their frugality. A potent engine can get a car moving with less effort, and thus, consume less fuel in the process.

And yet, powerful Altima engines, when matched with a lighter vehicle frame, can indeed lead to better fuel consumption.

Which is more efficient: diesel or petrol engines?

By and large, diesel engines have a leg up when it comes to efficiency, often using 20-30% less fuel than their petrol siblings.

Diesel engines generally offer more oomph at lower revs. But as with most things, there's a trade-off. Petrol engines in vehicles like the Nissan Altima have a zestier acceleration and overall dynamism.

The efficiency edge of diesel engines can be attributed to the fuel itself. Diesel, being denser, releases about 15% more energy when ignited. Plus, it's less fussy about the air-to-fuel ratio it needs to combust efficiently. This particular trait makes diesel engines run cooler and generally means they're a bit sturdier and have more pull.

So, when deciding:

• If it's pep and agility you're after, a petrol Nissan Altima might be the way to go;
• But if fuel economy and robustness take precedence, consider a diesel variant, if available.

How can one possibly elevate the mpg of the Nissan Altima?

Now, coaxing more miles per gallon from your trusty steed isn't as straightforward as one might hope. Many variables come into play – not least of which includes the conditions and specific model year of your Nissan Altima.

We're going to focus on some overarching principles here. Stick to these, and you might find your Altima suddenly becomes a tad more frugal at the pumps.

Maintain a dignified pace

Racing about like you're on a final lap at Silverstone will, unsurprisingly, make your Altima guzzle fuel. But dawdling at a snail's pace won't win you any eco-friendly badges either.

So, what's the golden ticket? Each Altima has a suggested "cruising speed" that's ideal for fuel efficiency. It's usually displayed on your dashboard, and sometimes even highlighted for extra emphasis.

Embrace cruise control

If your Altima is blessed with cruise control, deploy it, especially during those interminable motorway hauls. It finely tunes the fuel supply, ensuring consistent, efficient driving. Fewer pedal stompings mean fewer visits to the petrol station.

Engage the ECO-Mode

If your Altima model boasts an eco mode, give it a whirl. It's like giving your car a brief to sip fuel, avoid waste and basically, be a good global citizen.

Easy on the gas pedal

Thrusting your foot down like you're squashing a spider won't do your fuel consumption any favours. Imagine there's an egg beneath the pedal, and you're trying not to crack it. Delicate, smooth, and steady does it.

Keep the idling to a minimum

Even at idle, an Altima can get a tad thirsty. A 3-liter engine, for instance, could swig over a cup of fuel during a 10-minute idle session. If a long wait looms, consider shutting the engine down.

Resist the urge to turn off your Altima at every red light

There's a curious notion that shutting off the engine at each traffic light will magically save fuel. It's a tad misleading. True, you might save a drop or two if you're waiting for an eternity (let's say, 30 minutes). But, generally, restarting gobbles up more fuel than just letting it idle. Not to mention the wear and tear on the starter.

Use your judgment. If a long stopover is in the cards (5 minutes or so), then yes, power down. If it's stop-and-go, it's best to leave things be.

De-clutter Your Nissan Altima

Right, let's consider this. You're setting out for a long journey in your Altima, and of course, you'll be tempted to pack it with everything but the kitchen sink. Now, I love a good road trip as much as the next person, but think about the weight!

Every little extra, from that toolkit you never use, to the 17 umbrellas "just in case" - all add weight. Shed those extra pounds, and you'll notice your Altima sipping, rather than gulping fuel.

Keep an Eye on Those Tyres

Now here's a thought. Your tyres, as obvious as it might seem, play a pivotal role. A saggy tyre has a bigger footprint on the road and will drag your Altima down, making it work harder.

Ensure those tyres are pumped up to the recommended psi. It's an easy fix with profound effects on fuel consumption.

The AC Debate

It's a modern marvel, isn't it? But the air conditioner does put a load on your engine. Now, I'm not suggesting you melt in the summer. Instead, use it judiciously. Once the cabin is cooler, give it a break and enjoy the breeze from the windows. Then, when things get stuffy, switch it back on. It's all about balance.

Turn Off the Extras When You Don't Need Them

Power windows, heated seats, fancy lights - they all need energy. If you're running low on fuel and there's no station in sight, consider a temporary halt on these conveniences. But for goodness' sake, don't switch off your headlights at night!

Maintenance, Maintenance, Maintenance

Your Nissan Altima is like a musical instrument. It plays the finest tunes when it's well-maintained. Here are some key areas to consider:

Spark Plugs

A misbehaving spark plug can be the difference between a smooth symphony and a clunky rock concert. They ignite the fuel in your engine. When they're not working properly, you're basically pouring fuel down the drain.

Filters

Think of filters as the gatekeepers of your engine. When they're dirty or clogged, they restrict airflow or fuel flow, making your engine work harder. Keep them clean for a more efficient Altima.

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Engine Oil

Oil is the lifeblood of your Altima. It ensures all parts move smoothly. With regular oil changes, you're not just ensuring longevity but also optimal fuel consumption.

Engine Components: A Gentle Reminder of Ageing

You see, just as I may prefer a well-aged bottle of wine, engine components, much like humans, tend to wear out. Unfortunately, this natural process tends to result in some rather tedious problems like loss of power and increased breakdowns. Quite bothersome, really.

The poor Altima starts finding it a tad more strenuous to perform its quintessential functions, leading to – you guessed it – an uptick in thirst (or fuel consumption). If you, like me, have meticulously gone through each prior suggestion in this piece, yet still find your Nissan Altima's thirst unsated, perhaps there's a hint of critical wear on one of those engine bits. Let me elucidate:

• Cylinder-piston group wear. Exquisite features like burrs in the cylinders or perhaps even burned pistons, can make the Altima's heart flutter in all the wrong ways. This leads to, quite annoyingly, more fuel being sipped during its labours;
• Valve tribulations. Oh, valves. They can sometimes lose their charm and snugness. As the gap between them and their seating grows, you'll find more fuel prancing into the combustion chambers. The outcome? More fuel being consumed without giving back the oomph. Quite unfair, really.
• Concerns with root liners and crankshaft wobbling. Your Altima's crankshaft should exhibit the stability of an English gentleman – no unnecessary movement. Any unsolicited dance moves can result in wasted energy and, consequently, increased fuel consumption.

A Tad Too Much Enthusiasm in the Mix

Fuel, when mixed with air, orchestrates the harmonious ballet that keeps your Altima purring. This delicate blend needs the precision of a Swiss watch. A lean mix means not enough fuel, whereas a rich mix... well, it's like pouring an overly generous dram of whiskey. Quite wasteful.

If your Altima seems to gasp or choke, especially when you're being a bit spirited with the accelerator, and you witness an unsightly plume of black exhaust – well, there's probably too much excitement in the fuel mix. Culprits could range from a mischievous pump, a temperamental ECU, to even an injector throwing a tantrum.

Is Your Altima Giving You Subtle Hints?

Modern iterations of the Nissan Altima, like a well-tuned orchestra, have a plethora of sensors that diligently report any mischief. Keep a discerning eye on that dashboard. Any unsolicited light shows, particularly the rather ominous "Check Engine"?

Arm yourself with the trusty OBD-2 tool. If there's any mischief afoot, particularly from rogue sensors feeding tall tales to the ECU, you could end up with a rather thirsty Altima.

For The Tech-savvy: Programming Your Altima

Modern vehicles, including our dear Nissan Altima, come kitted with clever gizmos monitoring any aberrations. However, with the right tools, one can have a gentle chat with the Altima's brain. With a programmer – a nifty device that chats with the OBD-2 connector – you can delve into the world of engine management.

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Pair this device with your smartphone and, with caution, tweak to your heart's content. Mind you, with great power comes great responsibility, and while it's possible to coax your Altima into sipping less fuel by reigning in its enthusiasm, use this newfound knowledge wisely.

In Conclusion

While it might be tempting to embark on a crusade to extend every drop of fuel in your Altima, remember, every car, much like a fine instrument, needs a touch of care, understanding, and sometimes, a sprinkle of technical wizardry. Drive safe and may your Altima always find the perfect harmony between performance and efficiency.