Fuel - Premium only?
- Thread starter ET2041
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- '25 LC 1958 || '25 Sequoia LTD TRD || '05 TJR || '24 Polaris Ranger 1000 Crew
They won’t find that out, and neither will your engine absent a tune to utilize the increased octane. Realistically, you’re just wasting your money, but you also aren’t doing any harm.
Edit: Just saw you’re out of Kuwait. I can’t/won’t postulate on your spec’s fuel requirements, but can only state that anything in excess of your spec’s recommended octane level would be consistent with what I said originally.
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No "chip in the armor". I do not think that Toyota "is exclusively motivated by maximum performance and vehicle health/longevity." I do not care what their motivation is, although, I'd bet anything that a major motivation is to turn a profit building and selling automobiles.
That is most likely 95 octane in RON scale, which would be ~91 in US octane scale (AKI). 95 octane in US scale would be around 100 octane in RON.
I was just going to go there. Not for your benefit as you understand, but for others:
Octane rating - Wikipedia
^^ this link breaks down how octane specs are arrived at...for North American markets. Leave that market and some research might be required to see how a given vendor in a different market arrives at the octane listed on the pump.
When fuelling up in Europe years ago (and after I got over sticker shock at the prices), I noticed their octane numbers didn't correspond to what I was used to seeing in North America. Different regions can and do use different methods to arrive at their advertised octane numbers.
Amount of octane in our gas
I was never too sure about the exact numbers but I just found this on the KNPC website: Ultra (Green): 98 Octane, 90 fils/Ltr Super (Gold): 95 Octane, 65 fils/Ltr Premium (Red): 91 Octane, 60 fils/…
248am.com
^^ there is a post here alluding to how the octane numbers are calculated in the Kuwait market
I only run top tier gas and am also of the opinion that I would rather run top tier regular versus no top tier premium. That being said I run top tier premium in my LC.
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I have almost 30k miles and have been using 87 since I bought it and no issues. I’ve used 93 back to back for a month and didn’t notice an increase in horse power or mileage. I get 25 mpg in summer and during northern VA cold winters I still got 22-23 mpg.
Needless to say, I’ve gotten an engine light on but it was completed unrelated to gas type.
How are you sure of that?
Even top fuels over time lose their "light ends" As it evaporates its octane falls. When using old fuel knocking can occur which may damage engine components. Using fresh fuels from busy fuel stations can help performance. As stated earlier the premium is recommended and not required by Toyota for the LC.
The intention is to not run poor fuels that may impact negatively your motor. Like all things the decision on which to choose is entirely up to your standards.
The intention is to not run poor fuels that may impact negatively your motor. Like all things the decision on which to choose is entirely up to your standards.
I got the engine light on when I installed a Bluetooth kill switch. Once I removed the kill switch and disconnected the battery, it never came back.
Here is a video that covers extensively Top Tier vs. not Top Tier, ethanol, and premium vs. regular.
It's not only about engine knock, there are many reasons why running Regular fuel in an engine that is tuned for Premium is a bad idea and will affect long term engine performance and longevity. Even if the same engine (in our case the T24A) is tuned to run on Regular in some vehicles, it doesn't mean that you can put Regular in the LC without changing ECU timing and fuel delivery parameters and not suffer long term consequnces.
It's not only about engine knock, there are many reasons why running Regular fuel in an engine that is tuned for Premium is a bad idea and will affect long term engine performance and longevity. Even if the same engine (in our case the T24A) is tuned to run on Regular in some vehicles, it doesn't mean that you can put Regular in the LC without changing ECU timing and fuel delivery parameters and not suffer long term consequnces.
I know that going higher won't get any advantage but in here 91 is the minimum available. and 95 is what came recommended from factory for the non-hybrid for our specs.
As someone above just informed me about that 95 RON is 91 in the US.
You are correct, just knew that. Why is every scale is different in the US than the rest of the world..
It is more likely a north American thing. Canada, US and Mexico all use AKI scale.
AKI is basically RON (research octane number) plus MON (motor octane number) divided by two. So basically AKI is the average of RON and MON measurements. RON measurement is taken on low a low RPM with variable compression. MON on the other hand is taken on a high RPM under load. So AKI actually gives a more realistic output as the average of best and worst case conditions.
The recommendation AND requirement is here.
Short answer is that “premium” is a Toyota recommendation. The requirement in the manual is “At minimum, the gasoline you use should meet the specifications of ASTM D4814 in the U.S.A..” This includes “regular” 87 octane in the USA.
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Go ahead & use your avgas - have fun w/ lead wiping out O2 sensor & cat
You cannot tune a Toyota ECU. Toyota can, & very rarely does (Tundra Performance Package). They use a closed system. All your so called tuners are putting interruption circuits between a sensor & faking the ECU reading that signal.
Not a tune.
Pretty sure Costco is having a big run on all this tin foil from all the conspiracy hats yall are sitting around making.
(Correction- on DI
Slippers, Jon & others, Thanks for keeping me straight. Typing faster than my brain is working. Still think there’s a shortage on tin foil on the shelves over a discussion that ultimately the engine sensors just adjust.)
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It isn't the gas that leaves the deposits, it's oil and contaminants that are in the air/gasses flowing around the intake. In traditional fuel injection gas sprayed into the intake manifold actually cleans the valves as it is sucked by them.
Regardless, ours isn't a simple direct injection but actually has both direct and traditional fuel injection. I heard somewhere that one is more efficient under some conditions and the other under others. Certainly Toyota must have had some good reason to add the expense of two fuel systems to this engine!
As either a primary intention or a convenient side effect, we shouldn't see the buildup associated with direct injection engines.
Now, back to your regularly scheduled argument about octane.
No it is not. The only thing ASTM D4814 dictates about octane rating is that gasoline sold in the US must has to have its octane rating tested and displayed. Toyota referenced it in the manual because it also sets standards for whole lot of more important stuff like detergents, amount of sulfur etc. it is not referenced in the manual for the octane rating.
About octane, ASTM dictates things like minimum MON value for AKI (so that manufacturers cannot cheat by having an excessively high RON value to compensate for low MON) and sell it as 91 octane.
Basically it doesn’t set a minimum octane, it only sets standards for octane levels, their testing and where and when they should be offered. There is high altitude economy fuel with 85 octane that would be ASTM compliant.
ASTM itself says a minimum octane cannot be defined at fuel level and it should be set by the car manufacturer…
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Wow very informative.
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