View Poll Results: OCTANE - Which gas do you put in your 3IS
I always use 91 or higher.
259
91.20%
I sometimes use 89 or 87.
3
1.06%
I always use 89.
6
2.11%
I always use 87.
16
5.63%
Voters: 284. You may not vote on this poll
OCTANE - Which gas do you put in your 3IS and why?(merged threads)
12-17-13, 12:48 PM
#31
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I just did my first 5000 miles service at my local dealership, and while I was waiting for my 3is. I had a conversation with another staff. He told me that I can use 87 octane/regular gas on our 3is!!??! I said on the owner's manual it said clearly premium gas only, but he said all of their Lexus vehicles can use regular gases, and it will work fine. He also told me that the reason that Lexus put Premium gas only on the owner's manual it was because Lexus is a premium brand , and they don't want to be cheap. But technically speaking, regular gas is fine with 3is....
I knew for sure that 87 will lose some HPs, but not sure if it will harm the vehicle. ANy one can help me out here, is this really true that we can use 87 on our 3is?
I knew for sure that 87 will lose some HPs, but not sure if it will harm the vehicle. ANy one can help me out here, is this really true that we can use 87 on our 3is?
12-17-13, 01:30 PM
#33
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I always use premium in cars that require premium. The last time I used regular was during the Northeast Sandy hurricane. Man, you almost immediately feel the power loss, and to top it off, the acceleration is sluggish. I feel that an extra 20 - 30 cents per gallon is worth it.
I also use BP stations. They are everywhere in NYC. They also have a credit card that gives you 5% back for gas. Basically every time I go to the pump, it is reduced by 10 cents per gallon.
I also use BP stations. They are everywhere in NYC. They also have a credit card that gives you 5% back for gas. Basically every time I go to the pump, it is reduced by 10 cents per gallon.
12-17-13, 03:28 PM
#34
I just did my first 5000 miles service at my local dealership, and while I was waiting for my 3is. I had a conversation with another staff. He told me that I can use 87 octane/regular gas on our 3is!!??! I said on the owner's manual it said clearly premium gas only, but he said all of their Lexus vehicles can use regular gases, and it will work fine. He also told me that the reason that Lexus put Premium gas only on the owner's manual it was because Lexus is a premium brand , and they don't want to be cheap. But technically speaking, regular gas is fine with 3is....
I knew for sure that 87 will lose some HPs, but not sure if it will harm the vehicle. ANy one can help me out here, is this really true that we can use 87 on our 3is?
I knew for sure that 87 will lose some HPs, but not sure if it will harm the vehicle. ANy one can help me out here, is this really true that we can use 87 on our 3is?
No they put Premium on the IS sticker because the engine has direct injection and a high engine compression ratio. Modern engines are very capable of using a lower octane because they can adjust for knocking and pinging but you do lose power and efficiency as well as reduce overall engine life and risk more carbon build up. The RX and ES, ESh and CT are the only Lexus's that say you can use Regular 87 because they are tuned for that. Everything else including the RXh requires premium.
12-17-13, 06:09 PM
#35
Lexus Test Driver
Its really tricky when it comes to what gas to use. There are some cars that have been DYNO proven that using 87 and 93 make little to no difference. When I had my honda, the V6 motors that run an almost similar compression ratio actually made more HP on 87 than it did on 93. Other motors like Mustang v8, VW turbo 5cyls, etc; there have been dyno proven up to 6hp difference when using 93 than using 87. I havent seen any dyno proven results for our lexus motors but i have used both on the 250 and there was barely any noticable difference. for MPG, maybe 2 or 3mpg less city but barely any when driving on the highway. I still got 28 mpg. I cant really comment about the 350
My suggestion is to do some research on your own and make your own educated decision about what gas to use in your car. YES you can use 87 but manufacturer recommends 91 or higher for optimal performance.
My suggestion is to do some research on your own and make your own educated decision about what gas to use in your car. YES you can use 87 but manufacturer recommends 91 or higher for optimal performance.
12-17-13, 06:24 PM
#36
Lexus Test Driver
i don't care what the tech says, i would never put anything but 91 in anything with 11.8:1 compression!
any why? it won't save you any money. what you save at the pump you end up spending with more frequent fill ups and worse MPG. might as well buy the good stuff and enjoy the performance and better running engine without the risk of pre detonation.
any why? it won't save you any money. what you save at the pump you end up spending with more frequent fill ups and worse MPG. might as well buy the good stuff and enjoy the performance and better running engine without the risk of pre detonation.
12-17-13, 08:46 PM
#37
Driver School Candidate
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In Australia there is a label on the filler cap that reads 95 or higher octane. Our regular pump gas here is 91 and there is usually 95 and 98 available.
I use BP or Shell 98 in my car. Mind you, it's 45 Celsius (113*F) here in the summer so a fuel more resistant to detonation isn't a bad thing.
I use BP or Shell 98 in my car. Mind you, it's 45 Celsius (113*F) here in the summer so a fuel more resistant to detonation isn't a bad thing.
12-17-13, 10:54 PM
#38
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I figure there is probably a good reason why they put it in the manual....My wife has an RX and it specifically states that 87 can be used. I don't think they would make it 91for the 3IS just because. I think it goes back to "just because you could doesn't mean you should".
12-17-13, 11:00 PM
#39
lmao what!!
No they put Premium on the IS sticker because the engine has direct injection and a high engine compression ratio. Modern engines are very capable of using a lower octane because they can adjust for knocking and pinging but you do lose power and efficiency as well as reduce overall engine life and risk more carbon build up. The RX and ES, ESh and CT are the only Lexus's that say you can use Regular 87 because they are tuned for that. Everything else including the RXh requires premium.
No they put Premium on the IS sticker because the engine has direct injection and a high engine compression ratio. Modern engines are very capable of using a lower octane because they can adjust for knocking and pinging but you do lose power and efficiency as well as reduce overall engine life and risk more carbon build up. The RX and ES, ESh and CT are the only Lexus's that say you can use Regular 87 because they are tuned for that. Everything else including the RXh requires premium.
But like hoovey said, these cars are designed and factory tuned for premium fuel. Can you run lower octane fuel, sure. but the result is your car wont perform as it should... (whatever salesman told you "its because its a premium brand" should be fired)
12-18-13, 12:11 AM
#40
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i don't care what the tech says, i would never put anything but 91 in anything with 11.8:1 compression!
any why? it won't save you any money. what you save at the pump you end up spending with more frequent fill ups and worse MPG. might as well buy the good stuff and enjoy the performance and better running engine without the risk of pre detonation.
any why? it won't save you any money. what you save at the pump you end up spending with more frequent fill ups and worse MPG. might as well buy the good stuff and enjoy the performance and better running engine without the risk of pre detonation.
Armed with that and Google, anyone can find out what grade gas is REALLY appropriate.
12-18-13, 01:21 AM
#41
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I wouldn't dare put 87 in mine. Sure, I could do that to save money. But if I was that concerned with not spending a lot on gas, then I would've gotten an economical car, not an IS. It makes no sense to me to limit the car's performance just so I can save on gas.
12-18-13, 07:35 AM
#42
I just finished my 4th tank of gas. The first time was filled from the factory. Got around 22mpg. 2nd and 3rd time, I never noticed I was filling regular just due to the nature I've always pumped regular by nature, so I never payed attention. Got around 22-23mpg. This time around, I used premium again and got 22-23mpg.
Never noticed any sluggishness or knock or weird engine noises... *shrugs*
Never noticed any sluggishness or knock or weird engine noises... *shrugs*
12-18-13, 01:28 PM
#44
I just finished my 4th tank of gas. The first time was filled from the factory. Got around 22mpg. 2nd and 3rd time, I never noticed I was filling regular just due to the nature I've always pumped regular by nature, so I never payed attention. Got around 22-23mpg. This time around, I used premium again and got 22-23mpg.
Never noticed any sluggishness or knock or weird engine noises... *shrugs*
Never noticed any sluggishness or knock or weird engine noises... *shrugs*
