How to Maximize Your Prius Fuel Economy - By Rick Kearney

If you own a Toyota Prius, one of the most important issues on your mind is most likely, “Why am I getting less miles per gallon than the car is rated for?”

The answer is actually quite complex. The solution is not.

The first point to remember is that the EPA mileage estimates are derived using pure gasoline. Consumer gasoline (that which is available on the open market for general use) contains up to 10% Ethanol. You can do nothing about this. EPA estimates are also done on a test track, not in “real world” driving situations. They do not take into account traffic, trains, weather, other drivers or the countless other factors we encounter in daily life.

Here are some tips to help maximize fuel economy. They are geared primarily for the Prius, but most work just as well on other cars.

Tip #1. Inflate your tires. Low tire pressure causes increased resistance and wastes fuel. Low tire pressure also causes excessive edge wear on your tires, shortening their life.

This sticker is located on the driver’s door opening. Note the recommended pressure is 35 front and 33 rear. This is the MINIMUM pressure that should be in your tires. On the sidewall of the tire is another number, 44 psi. This is the MAXIMUM pressure that should be in your tire. A tire with less pressure rides softer and uses more fuel. A tire with more pressure rides slightly harder and uses less fuel. Set your tires at 40 psi and watch your mileage increase!

Tip #2 Air Conditioning. Prius air conditioning uses electricity to turn the compressor, while conventional cars use a belt on the engine. When the compressor is running, it uses power. Power that comes from gasoline. Automatic air conditioning means the ECU (the computer) can turn the compressor off when less cooling is needed. Set your A/C to a level you find comfortable. 76 degrees is comfortable for most people. “Lo” temp setting runs the compressor much more and uses more power. Remember, everything that uses electricity uses more gasoline. The power has to come from somewhere! The gasoline engine supplies the electricity for everything on both Hybrids and Conventional cars. Headlights, radios, blower fans, all want their share of power.

Tip #3 Slow Down and Smell the Roses. Excessive speed uses more gasoline than anything else. “Jackrabbit” starts and hard acceleration combined with hard braking wastes fuel. Prius is designed to get the best economy in the city. Slow, easy acceleration means the car needs less electricity to get up to speed and therefore less gasoline. Coasting allows the gasoline engine to turn off and not use any fuel at all! Sitting at traffic lights, the gasoline engine will also shut off and save fuel. Driving at steady speeds between 30 and 40 mph allow Prius to opportunity to make use of the electric motors and not use the gasoline engine for additional power.

Tip #4 Avoid little trips. Some people tend to drive only 1-2 miles to the store then the car sits for an hour or more. Then they drive 1-2 miles home again and again the car sits. These trips do not allow the gasoline engine to be run to operating temperature. Therefore, the engine is never shut off during the travel times! Plan your trips to make them in one big circle. Make the best use of Prius’ capabilities.

Tip #5 Lighten the Load. The more weight you carry in the car, the more gasoline needed to move it down the road. Do you really need those golf clubs every day? What about that bag of clothes you will take to the Goodwill someday soon? Every little bit helps.

Tip #6 Oil Changes. Dirt doesn’t weigh very much. Dirty oil, however, weighs more than you think. Old oil has collected dirt from your engine and holds most of the small particles in suspension. Changing your oil can improve your fuel economy. Regular maintenance is important.

Try these tips and track your fuel mileage the proper way. Fill your tank and record the mileage on the odometer. Drive until empty then refill and record the mileage again. Calculate how many miles driven divided by the number of gallons of gasoline pumped. That is your proper mileage. Get 6-8 readings and find the average. Remember to always stop pumping fuel when the pump clicks off. Do not top it up. Be consistent.
And always remember to drive safely!

-Rick Kearney is one of three Toyota Certified Master Diagnostic Technicians at Earl Stewart Toyota and the dealerships Resident Hybrid Genius. Rick travels with Earl regularly on the Lecture Circuit dispensing advice and answering questions for Florida consumers about their vehicles. Rick is now in the process of training Palm Becah County first responders about hybrid vehicles so they may safely conduct their rescue operations.

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Nitrogen and Shark Cartilage

It’s been one year since Chuck Cohen, director of Palm Tran, Palm Beach County’s bus transit system, announced that he was testing the effectiveness of filling his bus tires with nitrogen instead of air.

At that time, he said the tests would take up to a year, and he promised to share the test results with me and everybody else.

Readers of this blog and my Hometown News column are familiar with two previous articles I wrote on nitrogen in tires: “Don’t pay for nitrogen in tour tires” and “Nitrogen scam foisted on Palm Tran.”

You can read or re-read both of those articles by clicking on my blog, www.EarlStewartOnCars.com (or go to the archives section on HTN’s Web site).
I also posted the “Consumer Reports” article, “Tires-Nitrogen air loss study,” from Oct. 4, 2007 on www.EarlStewart.com (click on nitrogen-filled tires information).

This one-year study is the strongest, most authoritative proof that there is no measurable advantage to using nitrogen instead of regular air in your tires.

I sent Chuck Cohen three e-mails, beginning last March, asking him for any information he might have about the results of his testing. I received no replies until he finally answered my last e-mail this morning, Sept. 12. He wrote, “I will get back to you in the next day or so with a longer response.”

I received the below e-mail from Mr. Cohen, just before the deadline for this column. It’s now clear to me why he did not answer my e-mails but it’s not clear why he did not publicly announce the six-month delay in testing as he did the earlier erroneous date.

“Sorry for any delay in getting back to you, but as you are probably aware, we had several major things going on over the last week or so, including a fare hearing on our proposed fare increase for our paratransit service, that had to take precedence.

“While we did publicly announce that we were going to be testing the use of nitrogen in 2007, the actual testing did not begin until 2008. That was due to a delay in getting the nitrogen units installed in our North County (WPB) facility until January 2008.

“Our fleet conversion then took approximately 30 days and our testing began in February 2008. Our current plans are to complete our testing by the end of January 2009.
“I will insure that you get a copy of the test data when the test is done and our results are written up. Thanks for your continuing interest in this project.”

I responded by asking Mr. Cohen the following four questions:

• When you “publicly announced” that testing would begin in September 2007 and would be completed within a year, why didn't you also publicly announce that testing was being delayed for six months?
• I e-mailed you in March asking you about the testing results while still under the impression, as was the public that the tests were in process. I e-mailed you two weeks ago, asking the same question and a third e-mail one week ago. Why did you not respond to my e-mails until last Friday?
• When will your tests that commenced last February be completed?
• Will you advise the public and me if you delay the testing again?

Remember that this test is being conducted at an approximately $65,000 taxpayer expense and it is being conducted months after the “Consumer Reports” study was already published.
There was another article in “The New York Times” within the last year that came to the same conclusion about nitrogen in tires being worthless. The author, Tim Moran, has asked me to keep him posted on the developments with Palm Tran.

In an e-mail from Tim this morning, he suggested that, in addition to profit, one of the reasons so many car dealers are selling nitrogen is that they believe it does customers’ tires no harm.
I e-mailed him back and said, “What these folks don’t understand is that there is a detrimental effect when you make people believe in a product that doesn’t work. Item No. 1 in your list is that ‘it does no harm.’”

Drivers should really check their air pressure at least monthly, but with the “magic nitrogen” in their tires, they probably won’t feel it’s necessary.

Shark cartilage is “harmless too,” unless you don’t see your doctor regularly for checkups because you believe you can’t catch cancer.

I checked with four different car dealers to see what they are charging for putting nitrogen in tires.

John Pierson Toyota of Stuart charges $50. They used to have an addendum label on all of their cars with a charge of $199 for nitrogen. I guess that was a little more than people were willing to pay.

Schumacher Infiniti and Royal Palm Toyota both charge $39.95 and Maroone Toyota in Fort Lauderdale charges $37.95.

Tire Kingdom is also pushing nitrogen and it appears as if most car dealers in South Florida are selling it, too.

One of the reasons I’m pressing Chuck Cohen, Palm Tran and Palm Beach County government officials for justification of using nitrogen in bus tires is the fact that their using nitrogen adds legitimacy to all of these service departments that are peddling a worthless product to you, the consumer and tax payer.

If Palm Beach County government officials give their tacit endorsement of nitrogen by continuing to use it in their bus tires, you can bet that every seller of nitrogen in Florida will tout this as absolute proof that nitrogen in tires gives better gas mileage and longer tire wear.

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