By writing this blog, I am not stating there is not a problem with the C-Max resulting in lower than expected MPG. I don’t know. Many owners of the C-Max Hybrid are reporting lower than the EPA MPG for the C-Max Hybrid, a story I first wrote about in November. The ConsumerReports tests brought it to the attention of the media in December and a class action lawsuit followed later in the month. I pointed out that the lawsuit had an error stating Hyundai sold the C-Max. I’ve also written a blog on understanding the EPA MPG measurement method. As I’ve written these blogs, I’ve written about methods to improve the MPG for C-Max drivers. I decided it was important to collect these ideas in one location. This blog will be continuously updated as information is obtained. Please add suggestions for obtaining better MPG in the comments.
Understand the Instrument Panel Displays.
Use the Brake Coach.
Use EV+ and ECO Cruise Control. Do not turn them off. Let the C-Max learn common GPS locations to improve MPG.
Learn “Pulse and glide” and other techniques that hybrid owners use to get better MPG. The effectiveness of these methods could vary depending on the hybrid. I have not tested them with the C-Max Hybrid or Energi. A good article for ideas is, “Hypermiling (Saving Lots of Fuel) in a Hybrid; How to Get Maximum Fuel Mileage From Your Hybrid.” Another good blog on improving fuel economy, “Beating the EPA – The Why’s and How to Hypermile”, was posted by Wayne Gerdes at CleanMPG.com.
Do not drive aggressively. This includes accelerating rapidly from a stop, braking hard at the last possible second, and weaving to change lanes to get around other cars. Aggressive driving can lower gas mileage by 5 to 33 percent. Anticipate traffic conditions, curving roads, and traffic lights to minimize braking. Let up on the gas pedal early to minimize braking.
Slow down to the speed limit. Speeding can affect fuel economy by 7 to 25 percent. MPG decreases rapidly at speeds above 60 mph. It appears as though there is a big difference with the C-Max driving at 60 and just a few mph faster, e.g., 64 mph. The C-Max Hybrid cannot drive more than 62 mph in EV mode. The C-Max Energi can drive up to 85 mph in EV mode. However, driving at high speeds will still use kWh much faster than lower speeds with the Energi. Reducing your speed from 65 to 55 mph can improve your fuel economy by 10 to 15 percent. Reducing your speed from 70 to 55 mph can improve your fuel economy by 25 percent.
Remove excess weight. Excess weight can reduce mpg by 1-4 percent per 100 pounds. It affects the C-Max more than large vehicles.
Use cruise control. Maintaining a constant speed will save gas in most instances. When driving with cruise control, it is easier to control the maximum speed too. The C-Max will display the mpg while driving. To maximize fuel efficiency, set the cruise control speed within the legal speed limit to maximize the mpg on the display.
Use the air conditioner only when needed. Using the AC reduces fuel economy by up to 15 percent. In a city, roll down windows and turn the AC off. Driving above 50 mph with the windows down will increase drag and decrease fuel efficiency more than using the AC. When using AC, the recirculation setting reduces the air that must be chilled from outside the car. Using just the fan to circulate unchilled air is more efficient than using the AC.
Start driving when the engine starts. Modern engines do not need to warm up. The car warms up faster when the car is running. However, the engine is most efficient when warm. Combine trips when possible to avoid infrequent short trips starting with a cold engine.
Keep the tires properly inflated. Michelin Energy Saver Tires should be on the car when you buy it. There is a discussion of other tires that may be far less fuel efficient being used on some new cars at the PriusChat forum.
Perform scheduled maintenance.
Do not add external accessories which can affect aerodynamic drag. Bike carriers, luggage racks, and flags increase aerodynamic drag and lower MPG. Driving with your windows open above about 50 mph will increase aerodynamic drag and decrease MPG. The advantage of using the A/C less will be lost to worse aerodynamics for the car.
After your engine warms up, drive it. There is no need to let it warm up.
Now, as Daniel Gray of MPGOMatic.com said in a video, “Get your foot off the gas and let gravity do it’s work.”
This article was first published on January 5th, 2013. It was updated on January 16th, 2013.