At the start of January, we told you about the owner of a 2006 Honda Civic Hybrid who was taking the Japanese automaker to the small claims court

Heather Peters, alongside other owners who are filing similar class-action lawsuits against Honda, all claim that their Honda Civic Hybrids cannot achieve the gas mileage official EPA ratings say is possible. 

But when a car underperforms on gas mileage, who is really to blame? Is it the EPA, the automaker, circumstance, or something else? 

EPA Tests Vary Greatly. 

When the 2006 Honda Civic Hybrid was given its EPA ratings, the EPA Gas mileage tests not geared towards modern cars. As a consequence, gas mileage results were often much higher than they were in the real-world. 

Since then, the EPA has revamped its entire testing practices to better reproduce modern driving styles and conditions. In fact, as a consequence of the EPA tests being revised in 2007, the EPA reissued new gas mileage calucations for cars made before 2007.

This reduced the official EPA rating for the 2006 Honda Civic Hybrid from 50 mpg combined to just 42 mpg combined.

With so many different types of cars on the market today however, producing accurate gas mileage figures is inherintly difficult, unless EPA testing is modified to include longer-range tests using real-world drivers in real-world situations. 


EPA gas-mileage label (window sticker), design used starting in model year 2013

EPA gas-mileage label (window sticker), design used starting in model year 2013

Honda's Software Update

But this court case isn't just about gas-mileage window-stickers. According to Peters, the court case is also about a software update applied to her car which suddently dropped the car's displayed gas mileage by substantial figure. 

Honda claims the update was an essential softare update designed to prolong the life of the Honda Civic Hybrid's on-board battery pack. After the update, the on-board battery management system changed the way it managed the battery pack health, reducing the ammount of power that the battery pack could provide to provide assistance to the car's gasoline engine in the interests of longevity. 

Peters claims this software update, along with sales brochures which advertised a combined fuel economy of 50 mpg combined, purposely misled customers. 

However, in 2006, the EPA's official rating for the 2006 Honda Civic Hybrid was 50 mpg, and the software update -- designed to ensure long-life from the car -- had not been applied.  As a consequence, we can't help but think Peters' claim will be ignored.

It isn't Just The EPA And Honda.

Tips for better gas mileage - based on $3.85/gallon - from CFA

Tips for better gas mileage - based on $3.85/gallon - from CFA

However, despite how cleverly engineered it may be, a car is just a machine. 

Like any machine, cars are designed and built to operate at peak efficiency in a given set of circumstances. 

How the operator chooses to use that machine is beyond the control of the automaker. 

And while we acknowledge that some automakers aim to produce cars which get the best possible EPA ratings above everything else, real-world gas mileage is effected by real-world situations.

In fact, fuel economy is affected by how well you look after your car and tires, how fast you drive, how smoothly you drive, traffic and weather conditions, and how heavily laden the car is. 

In other words, if a car isn’t driven according to the best practices of economical driving, it may not achieve the same gas-mileage figures as the ones obtained in an official, EPA gas mileage test. 

Who Is Really To Blame?

We’re not lawyers, nor do we claim to be. But from an industry standpoint, all three parties detailed above have a part to play in improving gas mileage. 

Drivers need to become better at efficient driving, automakers need to become more transparent about software updates and advertising, and gas-mileage testing needs to better replicate the real-world.

As we've said many times before: real-world gas mileage is subjective, and EPA ratings should only ever be used as a rough indication of range or fuel economy. 


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