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Kia Forte Regular Or Premium Gas : Which One Should You Use? [ We Answered ]

Kia Forte Regular Or Premium Gas : Which One Should You Use? [ We Answered ]

I have been in the auto industry for about three decades in a consultancy role and have helped thousands of people with specific questions regarding different car models and makes.

And today, we’ll be discussing Kia Forte.

Kia Forte’s first model came into existence in 2009. It’s a good compact car and quite affordable, too. It’s an easy-to-drive car that will exceed your daily commute needs.

But as with any other cars, many motorists are undecided on what gas to use on their Kia.

What Type of Gas does Kia Forte Use: Regular or Premium Gas?

All Kia Forte generations use regular unleaded gas of 87 pump octane rating with less than 15% ethanol content. The gas type allows all the Kia Forte models to produce excellent performance with the best fuel economy score. (1)

But I recommend reading your vehicle’s manual to know the exact fuel specification. 

Pumping premium gas to a Kia Forte model won’t improve its performance since the optimized engine is compatible with regular unleaded gasoline. But you will spend more money and experience a low fuel economy score.

Premium fuel has a higher octane rating than regular unleaded gas. It implies that your Kia Forte will consume more gasoline due to the higher combustion rate. But premium gasoline has a better gas mileage than its unleaded counterpart.

Most Kia Forte models have a low engine compression ratio compatible with regular unleaded gasoline due to the slow combustion rate. Premium gas is suitable for engines with a higher compression ratio due to its fast burning time.

The golden rule is to read the manual guidelines after buying a new Kia Forte model due to the dynamics in the motor industry. It will help you decide whether to use regular unleaded or premium gasoline.

Both regular and premium gasoline for Kia Forte comes with advantages and disadvantages. But they are combustible and come from high-quality refined crude oil. Price and octane rating helps tell the difference between these two types of gasoline.

You can use regular and premium gas interchangeably on your Kia Forte model without damaging the engine. If you hear knocking sounds after filling the car, evacuate the fuel and stick to the option that does not cause any weird noise.

What Type of Gas Should You Not Use on Kia Forte?

Many gas stations have multiple options for filling up Kia Forte models. Every driver needs to make an informed decision to avoid spending more and damaging the engine. I recommend reading your vehicle manual to know the exact fuel specification.

Understanding different gas types for Kia Forte will help you save money and avoid unnecessary engine repairs. The octane ratings and engine compression ratio are crucial determinants for choosing the correct gas type.

Below are gas types not to use on any Kia Forte Model:

Octane Rating Less Than 87

Kia Forte engines are compatible with unleaded gasoline with an octane rating of 87. The rating value measures how the fuel burns in the engine while driving.

If the octane rating is less than 87, the engine will experience constant knocking due to compression resistance. The compression resistance and knocking will damage the engine.

If the octane rating is 92 and more, the vehicle might explode since the high combustion rate might overwhelm the engine.

Fuel with Methanol Traces

Kia Forte engines are incompatible with gasoline containing wood alcohol traces. These ingredients will damage vital engine components and reduce the car’s performance.

Methanol traces usually deposit on the fuel system and clog the engine control unit. Avoiding these gas types will help increase your engine lifespan and vehicle performance.

I recommend using clean and high-quality unleaded gasoline to prevent damage to the engine control system. It will also help save on money due to minimal engine repair.

Gasoline Mixed with Additives

Any Kia Forte model using gasoline mixed with additives experience engine misfiring and poor acceleration. These additives usually clog the engine and cause abnormal corrosion.

Examples of these additives are silicon, manganese, and ferrocene. These metals flow through the engine system to cause misfiring, stalling, and catalyst melting.

I recommend avoiding gas stations that blend their fuel with additives. It will save your vehicle performance from deteriorating and increase the engine lifespan.

Leaded Fuel

Pumping leaded gasoline in your Kia Forte model will damage the catalytic converter to cause an emission control system breakdown.

Leaded fuel emissions can also cause heart diseases, kidney issues, reduced fertility, and high blood pressure (2). EPA does not recommend the use of leaded gasoline anywhere in the USA.

Kia Forte fuel tanks have specific nozzles compatible with unleaded gasoline only. The fuel tank specifications help avoid inappropriate fueling.

Low-Quality Additive Detergents

Gasoline with additive detergents helps reduce carbon buildup and prevent engine damage. But Kia recommends using high-quality additive detergents over their low-quality counterparts.

Treating your gasoline with low-quality additive detergent will inhibit airflow in the engine control system resulting in excess carbon emissions.

It will also cause low fuel economy scores and environmental pollution. I recommend treating the gasoline with a Top Tier Detergent to avoid these issues. (3)

Flex-Fuel Type

Most gas stations label flex-fuel type as E85 since it contains about 85% ethanol. All Kia Forte models require unleaded gasoline with less than 15% ethanol content.

E85 gas will damage your Kia Forte fuel system and hinder engine performance since excess ethanol in the fuel will attract more water to facilitate corrosion.

Besides that, high ethanol content in the fuel will result in less energy production to propel your vehicle. Flex-fuel is only compatible with flex-fuel vehicles except for Kia Forte models.

MMT Rich Gasoline

Many cartels add methylcyclopentadienyl manganese tricarbonyl in gasoline to boost its octane ratings. But these ingredients are harmful to the environment and engine control system. (4)

Vehicles using gasoline rich in MMT tend to cause air pollution. Besides that, the manganese deposits on the engine lower its performance and cause emission system malfunction.

Check light will appear on the dashboard of your Kia Forte due to the impact of fuel mixed with MMT. Seek professional assistance to help evacuate the gasoline from your car.

Gas Type for Kia Forte by Year

2010-2013 Models

These models have a 1.6L, 2.0L, or 2.4L engine compatible with regular unleaded gas. Each engine gives different performance and gas mileage due to the varying sizes.

2014-2018 Models

These Kia Forte models have either a 1.6L or 2.0L engine that gives different gas mileage in the city and highway. The manual transmissions work well with regular unleaded gasoline.

2019-2021 Models

These Kia Fortes come with a 1.6L or 2.0L hybrid engine optimized for regular unleaded gasoline. But the Kia Forte FE model can run on premium gas of 91-92 octane ratings.

How Much It Cost to Fill Up Kia Forte

The average cost for filling a 2020 Kia Forte is about $61. But every state has a unique price charge due to various factors. (5)

California is among the few states with higher petrol prices. It will cost you about $64 to fill up the 2010-2013 Kia Forte models. The average gas price for the same model in Mississippi is $41.

Gas shortage and inflation are among other factors determining gasoline prices in the United States of America. I recommend accepting the current gas prices in your locality.

Beware that premium unleaded gasoline is super expensive compared to its regular counterpart. But the gas type does not offer any additional advantages to the vehicle.

Use regular unleaded gasoline since it is compatible with Kia Forte engines. Besides that, it will help save on money per gallon.

What’s the Kia Forte Gas Tank Size?

Kia Forte models come in four generations with different gas tank sizes. The fuel tank has undergone modification since the Kia Forte’s inception in the market. (6)

2010-2013 Kia Forte models are the first generations with a fuel capacity of 13.7 gallons (62liters). If you have a Kia Forte Coup 5, it has the same gas tank capacity.

The 2014-2018 Kia Forte Models are the second generation with a gas tank size of 13.2 gallons (60 liters). The 2019-201 Forte models are the last generations with a fuel capacity of 14 gallons.

Use regular unleaded gasoline to fill these tanks since all the Kia Forte engines have a low compression ratio. The gas type will enhance excellent road performance.


The optimized engines in all Kia Forte models are compatible with unleaded gasoline. But unleaded gas can either be premium or regular.

Premium unleaded gasoline is suitable for vehicles with high compression ratios and performance. A regular unleaded counterpart is ideal for low compression ratio engines.

Kia Forte engines have low compression ratios making them more compatible with regular unleaded gasoline of 87-90 octane ratings.

Premium gasoline will increase the risk of vehicle explosion due to high octane ratings and the inability to withstand the high engine pressure.

I hope this information will help you make the right choice. Feel free to share the article with your friends or family. You can also share your experience in the comment section below.