What fuel grade are you using in your RX350?
#436
2021 RX350 F-Sport fully loaded.
I have first-handed results I can share and these are time-tested:
* 87 grade gas - 17.5 mpg average
* 91 grade gas - 21 mpg average
All driving styles, modes, etc. remain steady. Here's the catch...
The 91 grade gas took 3 full tanks before MPG climbed up, so computer is being conservative with adjusting timing for 91. But quick to adjust down for 87.
Normal and Sport give similar MPGs.
Normal mode is more tolerable with 91 gas, again, after 3 tanks.
Sport mode is my preferred, but wish gears 3/4/5/6 were less aggressive. Like someone said, we need a mix between Normal and Sport, lol.
For everyone who says Lexus designed this for 87, wake up...they made it compatible for 87, but was designed for 91. Look at the compression ratios.
I have first-handed results I can share and these are time-tested:
* 87 grade gas - 17.5 mpg average
* 91 grade gas - 21 mpg average
All driving styles, modes, etc. remain steady. Here's the catch...
The 91 grade gas took 3 full tanks before MPG climbed up, so computer is being conservative with adjusting timing for 91. But quick to adjust down for 87.
Normal and Sport give similar MPGs.
Normal mode is more tolerable with 91 gas, again, after 3 tanks.
Sport mode is my preferred, but wish gears 3/4/5/6 were less aggressive. Like someone said, we need a mix between Normal and Sport, lol.
For everyone who says Lexus designed this for 87, wake up...they made it compatible for 87, but was designed for 91. Look at the compression ratios.
The following 2 users liked this post by Haibert:
Mikes94GS3 (02-05-24),
mrdeezy (04-21-24)
#437
2021 RX350 F-Sport fully loaded.
I have first-handed results I can share and these are time-tested:
* 87 grade gas - 17.5 mpg average
* 91 grade gas - 21 mpg average
All driving styles, modes, etc. remain steady. Here's the catch...
The 91 grade gas took 3 full tanks before MPG climbed up, so computer is being conservative with adjusting timing for 91. But quick to adjust down for 87.
Normal and Sport give similar MPGs.
Normal mode is more tolerable with 91 gas, again, after 3 tanks.
Sport mode is my preferred, but wish gears 3/4/5/6 were less aggressive. Like someone said, we need a mix between Normal and Sport, lol.
For everyone who says Lexus designed this for 87, wake up...they made it compatible for 87, but was designed for 91. Look at the compression ratios.
I have first-handed results I can share and these are time-tested:
* 87 grade gas - 17.5 mpg average
* 91 grade gas - 21 mpg average
All driving styles, modes, etc. remain steady. Here's the catch...
The 91 grade gas took 3 full tanks before MPG climbed up, so computer is being conservative with adjusting timing for 91. But quick to adjust down for 87.
Normal and Sport give similar MPGs.
Normal mode is more tolerable with 91 gas, again, after 3 tanks.
Sport mode is my preferred, but wish gears 3/4/5/6 were less aggressive. Like someone said, we need a mix between Normal and Sport, lol.
For everyone who says Lexus designed this for 87, wake up...they made it compatible for 87, but was designed for 91. Look at the compression ratios.
#438
I had mine for nearly a year before I saw the little sticker saying "Premium only", I had been using 87. I tried premium for several months and went from about 24 mpg to 21, no difference in power, didn't run any better, just seemed thirstier on the same trip I'd taken daily for months. I went back to 87 when 50 cents more per gallon became 80. Certainly wasn't worth the extra cost then. Maybe 87 is fine in an older hoopty that probably doesn't have the higher compression it once had.
The following 2 users liked this post by treefiddy9:
autotech13 (04-22-24),
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#439
2021 RX350 F-Sport fully loaded.
I have first-handed results I can share and these are time-tested:
* 87 grade gas - 17.5 mpg average
* 91 grade gas - 21 mpg average
All driving styles, modes, etc. remain steady. Here's the catch...
The 91 grade gas took 3 full tanks before MPG climbed up, so computer is being conservative with adjusting timing for 91. But quick to adjust down for 87.
Normal and Sport give similar MPGs.
Normal mode is more tolerable with 91 gas, again, after 3 tanks.
Sport mode is my preferred, but wish gears 3/4/5/6 were less aggressive. Like someone said, we need a mix between Normal and Sport, lol.
For everyone who says Lexus designed this for 87, wake up...they made it compatible for 87, but was designed for 91. Look at the compression ratios.
I have first-handed results I can share and these are time-tested:
* 87 grade gas - 17.5 mpg average
* 91 grade gas - 21 mpg average
All driving styles, modes, etc. remain steady. Here's the catch...
The 91 grade gas took 3 full tanks before MPG climbed up, so computer is being conservative with adjusting timing for 91. But quick to adjust down for 87.
Normal and Sport give similar MPGs.
Normal mode is more tolerable with 91 gas, again, after 3 tanks.
Sport mode is my preferred, but wish gears 3/4/5/6 were less aggressive. Like someone said, we need a mix between Normal and Sport, lol.
For everyone who says Lexus designed this for 87, wake up...they made it compatible for 87, but was designed for 91. Look at the compression ratios.
In Australia ALL Lexuses are 95 RON minimum, no mention anywhere that Standard fuel is okay. The RX is THE big seller in the USA, but it is also not good on fuel, so they made the decision to state your 87 AKI is okay, people see this and think it's cheaper to run. The USA is very fuel price sensitive, much more than Australia.
#440
I have had my 2016 RX350 since new.
193,000km or 120,000 miles
lifetime overall fuel economy average on regular gas (87) = 10.5 L/100km or 22.4 mpg
Based on that I used 20,265 Liters of regular gas.
In my area premium gas is $0.20 - $0.3 more per liter. About 15% more than regular.
That would have equated to about $5000 more that I would have had to pay.
For me premium would have never provided enough fuel economy improvements to offset the price premium.
193,000km or 120,000 miles
lifetime overall fuel economy average on regular gas (87) = 10.5 L/100km or 22.4 mpg
Based on that I used 20,265 Liters of regular gas.
In my area premium gas is $0.20 - $0.3 more per liter. About 15% more than regular.
That would have equated to about $5000 more that I would have had to pay.
For me premium would have never provided enough fuel economy improvements to offset the price premium.
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#441
From my understanding, you would just have the computer adjust your KCLV to be higher until it detects knock from what I've seen when tuning on 87 and 93 octane levels. So you would get a little power gain but should get the same MPGs as before unless you're running on ethanol like my car is then that's a different story. However, tuning for a higher octane rating can certainly gain more power from your car.
#443
#444
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Pierre5355 (05-09-24)
#445
As previously mentioned, your car will adjust ignition timings until you run into knock but you can run either 87 or 93 octane, with the computer adjusting the knock correct learn value accordingly to be either higher or lower until it runs into knock. However, without a specific tune for it, you won’t fully reap the benefits of using 93 octane. Furthermore, the method of calculating fuel ratings in the US differs from that in other countries, so a 95 RON rating elsewhere equates to a 91 octane rating here.
#446
I am using 91. I don’t care what anyone else says. I don’t expect any magical results. 87 is for lower compression engines and or cheaper cars. 87 seems safe for this car, Every premium car I have driven in the last 20 years requires premium. I just can’t put in 87. Its not worth the 20 cents a gallon to play games with to me. You better hope your knock retards work if you are on 87 and climbimg a mountain in the hot summer.
The following 2 users liked this post by mrdeezy:
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#447
I live in the Colorado mountains and always go to Costco and buy their 85 octane fuel. I have 85000 miles on the car and it drives like new. I have more than enough power to fly up any mountain pass. To each his own.
#449
I am using 91. I don’t care what anyone else says. I don’t expect any magical results. 87 is for lower compression engines and or cheaper cars. 87 seems safe for this car, Every premium car I have driven in the last 20 years requires premium. I just can’t put in 87. Its not worth the 20 cents a gallon to play games with to me. You better hope your knock retards work if you are on 87 and climbimg a mountain in the hot summer.
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autotech13 (05-09-24)
#450
Your car should run fine with 87 and 93 since there's a sensor to retard/advance timings if it does/doesn't detects knock, and don't run e85 without a tune/long periods of time lol.