88 Octane for 2010 Prius - What's up with that?

Agreed

 

I would hope that Toyota provides a sticker for the manual that the service dept at the dealership puts in the manual or maybe on the incorrect page or on the front of the manual that says 87 Octane fuel.
Not all dealers are honest. I'm not going to worry about it tho.

 

:deadhorse:

 

I wonder if actual octane in the fuel stations is really that precise that it would be exactly the number listed on the pump anyway. There could easily be a +- 1 octane either way. They really should be erring on the + side if anything so they never have less than the listed minimum octane on the pump label.
I would hope the cars are not so delicate to be damaged by a one octane offset.

 

Has the 88 octane question been resolved by the Prius Team?

 

yes, see this post above:

http://priuschat.com/forums/2010-toyota-prius/61874-88-octane-2010-prius-whats-up-2.html#post858305

 

Yes:

RTFT!

 

Thanks for the quick reply!

 

So far 87 octane, reg gas, is all we have used in our 2010 Prius III with Navi for over 2,300 miles.

Car runs great and no problems at all.

Alfon

 

...wait. I have to pay to view this information? Wth???

 

Your 2010 Toyota Prius Owner's Manual is available in searchable PDF files on Toyota Owner's Online for free.

Once you have your VIN and dealer info, you can register for free on Toyota Owners Online and access the 2010 Owner's Manual (among other good stuff there like your maintenance schedule).

Presumably, the 2010 Prius Owner's Manual has been or will be similarly revised on Toyota Owners Online.

 

I doubt it really matters if you used 87 or 89 octane, the 2010 manual says 88 or higher. If you were really concerned do 5 gallons 0f 87 and 5 gallons of 89 and you have 10 of 88.

I used 89 octane on first fill up. I question about the post above that said using higher octane would give worse milage per gallon? I find that hard to believe. Guess I'll have to do a 94 octane fill up as a research project and see what happens.

 

the whole saga of is it 88 or 89 or 87 has been put to bed. It says 88, in error, confirmed by toyota, it should say 87. use 87.

 

Genius.

Definitely a legitimate question, but it has been answered. Running around for the Japanese version of the manual to cross check borders on full-blown O.C.D.

 

I was confused because around here (Denver, Colorado) 85 is "regular" octane. Here's what I found on Wikipedia, for others in higher altitudes:

In the Rocky Mountain (high altitude) states, 85 AKI is the minimum octane, and 91 AKI is the maximum octane available in fuel. The reason for this is that in higher-altitude areas, a typical combustion engine draws in less air per cycle due to the reduced density of the atmosphere. This directly translates to reduced absolute compression in the cylinder, therefore deterring knock. It is safe to fill up a car with a carburetor that normally takes 87 AKI fuel at sea level with 85 AKI fuel in the mountains, but at sea level the fuel may cause damage to the engine.

 

No need to question it. Higher octane gas requires a higher temperature to burn. It's nothing more than a safety feature for high compression vehicles. Many forced induction cars need to run premium to prevent detonation, but most naturally aspirated engines are fine on regular octane. Running higher octane is only beneficial in a vehicle that is specifically tuned for that octane. Otherwise, the fuel in the cylinder simply takes longer to ignite during each cycle, resulting in (marginally) less power and (marginally) less fuel mileage. You can't harm your car by using premium, but for everyone who thinks that they are giving their car a "special treat" by filling up with premium when only regular is required, you're really just throwing your money away.

Source- Professional and hobbyist performance car tuner and mechanic.