2007 Prius Touring use to get only 38 to 40 mpg

No, its not. Higher octane fuel is harder to ignite, and prevents pre-detonation in high compression engines. If the engine is designed to use higher octane, it may run poorly without it. If its not, as is the case with the Prius, it won't make any difference.

 

If you want to waste your money on 91 Octane, go right ahead. It is not going to give you any better mileage. It is not cleaner either. It simply is a higher octane fuel. It is made for engines that "require" the higher octane rating.

The Prius is designed for 87 Octane fuel. Read the owners manual.

 

I agree 100% and it is a common misconception that is not helped with the way the fuel companies market their particular higher octane fuel. I say the same thing, if you want to waste your money on 91 Octane, go right ahead.

I wanted a definitive answer as I found as many for and against opinions when researching this very subject in forums all over the internet. So in exasperation I decided to do my own quantitive research to prove it to myself, as I was leaning towards the view that it might help. Even though I found myself starting to form the opinion the higher octane fuel was helping, when I actually analysed my Fuelly records, I found (comparing like-for-like, season-for-season) that higher octane fuel did no better and in some cases did worse, than the correct octane fuel as advised in the owner's manual.

Ever since I have only used the correct octane fuel and I am continually getting good to above average consumption figures, and presently am getting the best I have ever had.

Also, that once you eliminate all technical possibilities such as tyres (not using LRR), tyre pressures, 12v battery not holding charge, etc, I truly believe that driving style is the biggest impediment to achieving low fuel consumption.

I can see this in the consumption figures I get compared to my wife driving the same car over the same terrain. For one thing, I'm more patient and that helps. However, I do know that my current driving style infuriates some people, for instance, when they think I start letting up on the gas "far too early" in their opinion. But getting in those long glides really helps.

And don't get me wrong, I don't drive like some driver defect (not wanting to use terms like granny or similar as I don't want to offend), nor do I accelerate too gently.

So there you have it, my $0.02 worth. Hope that helps.

 

GJ! Thanks so much for this thread! I have a 2007 Prius Touring and am currently getting 37-40mpg.

I'm going to change the tire pressure tomorrow as someone else suggested, but was interested in finding some resources on how to:

1) Change the 12v battery; and
2) Cleaning the MAF filter

Any suggestions? Also....how is your 2007 doing now 3 months later?

 

BrentonJJ, you are aware that the "touring" unit's traditionally get a little lower MPG than the non touring, don't ya? Also, what make and model of tires are you running? Are they LRR type tires?

 

Thanks dorunon! I am aware the mileage is a little less on the touring. Do you know why that is? Larger tires? Bigger frame?

I don't have LRR tires. They are cheap Faulkner tires and were just recently replaced. I just bought the vehicle last week and they were replaced by the previous owner. Will look into some LRR's when these cheap ones are up, unless it is more cost effective to replace them now?

 

My understanding is the reduced mpg is primarily due to slightly wider tires on the touring model.

 

Meant to say Falken Tires earlier....

 

There is 90% of your problem right there.

The touring model has larger tires than the non-touring model. The larger diameter tires are less efficient than the smaller tires that come on the Prius. Running non-LRR tires will further decrease fuel economy and could end up costing you quite a bit in the long run. It all depends on how many miles you drive annually though. If the current tires are at 5/32 tread depth or lower I would just replace them now with a good LRR tire. If they are like new then I would just air them up properly and ignore the mpg indicator. Just know that the difference between a budget tire and a quality LRR tire can be as high as 5+mpg.

 

I have to agree with F8L on this one. Your Falken tires are your downfall. Touring or NON touring, running NON LRR Tires is a no no on the Prius. Always causes the MPG to fall.

I am running 17" Michelin Primacy's on the 2013 I am driving. My fuelly stats are current and are 100% accurate. Study the stats and you should then understand.

Dif between touring and non is a paltry two to three MPG when everything is right!

Ron (dorunron)

 

Thank you all for this thread. How does one tell if a tire is LRR or not?

Thanks

 

You can look up the model of tire in the specific size to see if it is rated as LRR. TireRack.com will show the rating as will the tire manufacturer. The problem is, all tires vary in rolling resistance so some are labeled LRR but are much less efficient than another tire with the same label. In the U.S. we don't have an official rating system for rolling resistance yet.

 

We just bought a 2008 Touring model with 58k miles. First tankful ended today with average MPG at 46.2. Approximately 210 of those miles were highway @ around 65 mph, and we did much better with the second half of the tank as we are starting to figure out the driving techniques that maximize fuel efficiency. Considering how hot it has been here in Virginia these past few days, requiring heavy a/c use, I have to say I'm very pleased with how our Prius is performing so far.

 

congrats and welcome! all the best with your new pri!

 

Prior to 1995 many Gas companies put more detergents in 91 than in 87,, but the US EPA mandated detergents in all gas in 1995.
Top tier gas has even more detergents in all grades than the EPA minimums.
Top Tier Detergent Gasoline - Wikipedia, the free encyclopedia

Today it is unlikely than any company has more detergents in 91 than 87. But it USED to be true.

Some cars are tuned for 91, if you use 87, it retards the spark advance to prevent pinging. The Prius* was tuned for 87 and does not do better on 91. In a separate issue, E0 gas tends to get 4% better mileage than E10 gas. In some locations, 87 is E10 and 91 is E0, but the difference in MPG is due to ethanol, not octane ratings.

*Some owners of the Prius c, which uses a different engine, think it is tuned for 91, I do not own one, so I can't contradict them.

 

Thanks! So far we're thrilled with our Prius. Moving to a smaller vehicle (it's replacing a Honda Odyssey) will take some getting used to, but aside from that it's an awesome car, and saving ~$1500 yearly on gas sure will be nice. Things are tight these days and every dollar helps!

 

congrats!