That will be in your manual. If it says 87 unleaded than anything above that is a waste of money.

 

100% correct - Vehicles that are designed to run on 87 octane, then using anything else is a waste.

 

It's another fuel thread!!!

Keep it simple, use either 87 or 89 octane. If you want to be really cool, you can use 91 or 93 octane but is is not required. For my Camry, I will usually use 87 octane but if I plan on traveling somewhere far I will use 89 octane on the way to but not back.

 

It's another fuel thread!!!

.

Yep. And just wait for another oil and Seafoam threads.





OP, it's 87. Eighty seven.

This question is not relevant in Highlander realm. It is in Lexus realm, when they decided to slap 92 requirement onto RXs then, in 2012, suddenly changed it - for exactly SAME engine as in 2011 or 2010 - to 87.

92 is now used ONLY on dem new turboed engines due to very high compression ratio they run at. So that 87 does not self ignite. Though I ran my NX200 with turbo on 87 without any "pinging". It's just more sluggish.

 

I've read that using higher octane gas allows the computer to advance the timing a bit beyond the design operating point. Reportedly that can have an adverse effect on engine durability over the long haul.

Higher octane fuel also has a slightly lower heating value than regular. Over the life of an engine that might add up to a extra few bucks spent on fuel.

I tend to always follow the manufacturer recommendation, except for oil change, transmission service and coolant flush. I do those more frequently than recommended.

 

With our Corvettes, using 93 octane and the spark gets the max advancement by design. Use lower octane and the spark is less advanced. So you might lose 5-15 HP at peak RPM.


I've never heard of higher octane fuel advancing the spark beyond design in any vehicle.

 

Just like brakes, fluids, suspension, use whatever you decide to use. Whether or not it helps is up to you and only you. I have a K&N CAI in my Camry. Is it faster? Nope but it sure feels like it. The myths for everything will always be out there. You can follow those myths or you can follow the manufacturers recommendation.

 

Just like brakes, fluids, suspension, use whatever you decide to use. Whether or not it helps is up to you and only you.

Whether something helps or not depends upon physics, unless it is a subject that cannot be measured by physics.

It reminds me of the first time I pump up a bicycle tire when I was about 6 years of age. Not only was I POSITIVE it was riding more smoothly, I felt that I was actually RAISED up higher off the ground. It wasn't until I took a peak at the rear tire as I was riding that I was informed it was dead flat.

Feelings lie. Physics is truthful.

 

The real thing to look for at the pump is if the gas is 90/10 ethanol, or unleaded, both with an 87 octane rating. You'll get better mileage with unleaded, but it usually costs 30-45 cents a gal more.

 

I've searched for ethanol-free gas for my generators ... it's hard to find ... https://www.pure-gas.org/

 

interesting that BMW recommends premium gas in the 3-series cars I owned, BUT if you look in the owners manual they show the formula used to calculate octane is the EUROPEAN formula, even in the US car owners manual. Converting the European formula to the US formula for octane showed that our US regular = European premium @ 87 octane US. So I always burned regular. I did try 2 tank fulls of premium "just to see", but there was absolutely no difference in performance.

Recently I went car shopping and was interested in the Equinox and Terrain. It's hard to find the details on this, but when equipped with the towing package (which I wanted), the 4 cylinder turbo engine is recommended to use premium (91 Octane). GM says you can use regular (or mid-grade), but if the engine knocks then use premium.

Now, a Honda Odyssey I once owned had some sort of variable timing where the computer would sense the octane and retard the timing if regular was used, reducing the power and gas mileage as a penalty for using regular. I don't know if Honda still does that, but that's a case where the octane really did make a difference. You could use regular and it wouldn't knock because the computer was controlling things appropriately.

One of the things I like about my 3.5L '18 Highlander is that is is specified for Regular (87 octane). At about $0.50 a gallon more for premium I would just be rolling up dollar bills and setting them on fire for no reason if I used premium in it. The HL runs great on regular.

 

Ok. So please use the ADVANCE SEARCH option on the top right of the 3rd Gen page to find numerous threads on this topic. Hopefully you can read through those instead of continuing another link and thread that basically will say the same thing in some different words.

Should I lock this?
(Where is FunMan1 with that cool CA-super-glue image?)

 

Regular, that's all this car needs. But really, do what makes you feel good. Just like I have a tendency to fill up at Shell vs other stations.

 

I thought I read gas with up to 15% ethanol ok in my HL. FWIW...No issues using E10 gas in my old Evinrude (late 80 model) 2stroke 15HP outboard motor. Do know my mpg dropped slightly on other rides I had at the time when mtbe was banned & ethanol was new additive. Can't compare now, but suspect same on my HL eng.

 

I thought I read gas with up to 15% ethanol ok in my HL. ...

Correct, it's in the Highlander Owner's Manual - Page 665.

 

Thanks for responding. I had no idea the HL can operate in both FI and DI modes. I guess skipping the drive through is skipping some valve cleansing benefits!!! I wonder what the DI and FI utilization %s are with my driving style, which is primarily eco or near eco. I guess we will never really know what defines FI over DI, aside from clear cut scenarios (e.g. towing uphill, passing zones, hard acceleration). For instance is anything the turns off the eco light on dashboard safe to say a true indicator of DI over FI? How about >3k rpms?? Or >2k rpms??

 

For instance is anything the turns off the eco light on dashboard safe to say a true indicator of DI over FI? How about >3k rpms?? Or >2k rpms??

That certainly sounds reasonable...ECO light off, DI only. But, I have no knowledge of the algorithm. It could be as simple as "cold" vs "hot" engine, with FI only used when the engine is cold.

 

As Blackheart mentioned, altitude and humidity also affect how vulnerable a combination of compression ratio and octane will be to pre-detonation.

So, if you visit Colorado, you'll see that our "mid-grade" is not 89...its 87. Our lowest grade octane is 85.

I have been using 85 octane on several Toyota 3SFE engines here in Colorado for almost 20 years, and those engines have a combined mileage of over 400K miles. Those engines have knock sensors and ECU controlled timing. I have had no issues, and no knock using 85, as we live at 6100' altitude, and most of the Front Range is over 5000' altitude. I don't notice any difference when I run 87 (but that engine is not exactly a powerhouse, haha). We also use 85 in an '13 Toyota Sienna, and there is no knocking.

I think you can get 85 in Wyoming, and 86 in South Dakota and Utah, but then as you head to lower altitudes, you can only get 87 octane as the lowest grade. This reflects the relationship between octane, pre-detonation, and altitude. I can't speak to "humidity" because we don't know what that is here in Colorado, lol.

 

One person mentioned ethanol. Ethanol increases the "octane" value and hence allows reaching some target, say 87. But ethanol does not have as great an energy content as "gasoline" so the E fuel will yield a lower mileage. I live in a state that gives a tax break for gasoline with ethanol. One rule of thumb here is if the price difference is less than fifty cents a gallon between the E fuel and unleaded at the same octane level, go with the non E gas and the higher mileage will offset the higher cost. Haven't actually tested the rule in my Avalon

 

The energy content difference was mentioned in a previous post, but a good point regarding offset between cost and gas mileage.

However any feedback regarding how engine pinging can be reduced with higher octane rating or if thats true at all.

 

Yes, IF the combustion chamber conditions allow for ignition of the fuel mixture prior to the spark firing, incrementally higher and higher Octane level fuel has the potential to stop that premature ignition. USUALLY, if it is just very mild ping, going up one rating will stop it. Or, a colder day, or a very humid day will even stop it. Or, just not putting as much load on the engine. These conditions don't damage the car.

Compression chambers are designed to have a flame-propagation sequence, or flame-front, that is conducive to better power. In the case of a severe hot-spot location somewhere away from the spark plug, which begins ignition at one point and the spark plug begins ignition at the other, the colliding flame-fronts can result in a actual "knock", which can be very destructive. In this case, slight changes in Octane aren't going to fix the situation. It will take a big jump. WHat is really needed is a cleaning of the combustion chamber, and/or, better air-fuel mixture/timing relationships.

The Turbo-charged engines are the ones that generally call for a higher octane. As the intake runners are pressurized by the Turbo, more air is shoved into the combustion chamber on the intake phase, which raises the resultant Compression chamber pressures, which increases the temperature as the piston rises, which tends to create the conditions that can ignite the fuel prior to the ideal spot in the piston travel.

 

Octane 87 is fine



mamaof2,

I own a 2013 Highlander LE AWD and have been using the 87 Oct from our local 711 Gas Station and my car is still working fine.

 

I have a 83 corolla 4ac 1.6 and the owners manual says 93 octane or above . Dont really know why it requires the higher octane but i run it anyway. Also i try to find 100% gasoline without ethanol as ive been told the ethanol is not good for the carburetor ....

 

Ethanol is absolutely terrible for older cars. Very hard to find premium fuel without ethanol around here. None ethanol is only sold as regular (87). Have a 72 Cutlass that takes premium. I have to buy additives to combat the stupid ethanol. Hate it.

 

has anyone here tried regular vs gas and see if in real life there was a difference if u got more miles out of premium by using the TRIP?

 

Premium does NOT give you better gas mileage or better performance if you vehicle is designed to run on 87 Octane. The name Premium is a marketing ploy to sucker people into paying more for it (I.E Higher profits for the gas company). Higher Octane prevents engine knock. That's it. So it will NEVER EVER make a car designed to run on 87 octane to go faster or get better gas mileage. Around here Higher octane gas sells for 50 cents more then regular. It costs the oil company about 5 cents more to make premium vs regular.


For cars that are designed to run on higher octane (notice I'm not calling it premium) - if you don't use the higher octane gas then when/if the engine knock sensor detects engine knock it'll send a signal to the ECU which will retard the timing a little. When this occurs it'll give the vehicle less performance and thus worse gas mileage. The WORSE case scenario is if the knock sensor fails when there's engine knock and engine continues to knock. It could destroy your engine. I've torn into an engine of a buddy of mine that this occurred when he was drag-racing. Two of the pistons had holes in them and the crank was broken in two.

 

Buying premium for a vehicle that runs on regular is like buying gluten free products when you don't have Celiac disease. Absolutely no benefit.

 

I have read many of the posts on this topic and wonder if anyone has any real facts. Mazda rates its CX9 engine at 227 HP with 87 octane and 250HP with 93 octane. OK so what's different about that engine and a Highlander's? A turbo...Higher Octane can take higher compression, producing more power....so that's half the story...the timing has to be retarded for the lower octane gas so it doesn't pre-ignite. That is done with a knock sensor that automatically retards timing when it senses knocking.
I did a little research and found or Highlanders also have a knock sensor...It's about 165 bucks. Interesting..why do we need that if we're all going to use the 87 Octane gas???? Is it possible that when we run 93 octane that the ignition timing changes allowing us to make more power? I haven't tried this on a Highlander, but I did try it on an old Celica that I put 165,000 miles on years ago. The car certainly had more spunk and about 2 more miles per gallon when I ran premium in her....She definitely had a knock sensor, and premium definitely made things better.
So believe what you want....I may try a test on my Highlander and will let you know the results.

 

Lower boost will also reduce the chance of detonation, later fuel timing, variable cam timing, etc., etc., etc. Do you really think Toyota is trying to trick you out of 7or 8 HP?

If you really want to know rent a couple of hours on the Dynomometer. No BS and you will get the straight fact.

 

Removed

 

Didn't read this whole thread, so I'm sorry if this reply is repetitive. With our stay-at-home orders and less driving being done there are more cars being driven less, and some being laid off for weeks or more. I think that using zero-ethanol fuel could be beneficial because it doesn't deteriorate as fast as ethanol "enhanced" fuel does. Plus it's a lot cheaper now than it used to be. I read somewhere that zero ethanol fuel is still good after a couple months, whereas 10% ethanol fuel deteriorates after one month. Plus, as the post above me implied, you will probably get better mileage when you do start driving again.

 

I don't find it insignificant at all, since I had a similar experience with a Celica, and let me tell you, mileage always dropped off in that car when I went to 87 octane. Also, it may not be true now, but premium fuels had more detergents....read better at keeping your fuel system clean...I've never had to replace an injector in my nearly 40 years of fuel injected Toyotas, and I keep them a long long time..I always figured premium fuel helped with that.
Anyway, I will drop to 87 and see what happens to my mileage.

 

I don't find it insignificant at all, since I had a similar experience with a Celica, and let me tell you, mileage always dropped off in that car when I went to 87 octane.

Then I suggest you take a class in statistics. Too many unknown variables for anyone but you find the data valuable.

 

While it’s seems simple that MPG is miles divided gallon, how you determine miles and gallons makes a difference. Is the car always level when you filled, does the tire always have the same air pressure so circumference is the same. Then other factors, density altitude and fuel energy density. That is, how many btu are in each gallon. A 30 mpg car that has a 3 mpg improvement is 10%, 2 mpg is ~7%. Density altitude by itself varies more than that day to day.
You must account for all those variables before you have information you can trust.
The best way to do that is on a Dynamometer. I can guarantee that if simply using 93 octane gave better fuel mileage all manufacturers would specify using for the EPA rating alone.

 

Mine goes faster when I wash it. And ludicrous speed when just waxed.

 

 

Well said.

 

we hope to do that here

 

we hope to do that here

Why would you do that? Difference between 87 octane @ $2.00 and 93 octane @ 2.40 -93 octane costs about 20% more.

Even if the 2mpg increase is true, it only yields a difference of less then 1% increase in gas mileage. So at best case scenario you'd be loosing money.