Gas
Driver School Candidate
Joined: Jul 2018
Posts: 49
Likes: 2
From: Ontario
No, unless it's the absolute only fuel available and you don't want to get stranded. If you don't run 91, you'll likely get worse fuel economy and can end up with other issues that will cost you money offsetting any savings from running cheaper gas. And power will be reduced.
Moderator
Joined: Nov 2016
Posts: 9,597
Likes: 4,787
From: GA
It's a valid question, since some cars "recommend" premium but do not require it. However, the owner's manual for the IS 300 states that premium fuel is required. If you must use 87, it is recommended to fill up with 91 as soon as you empty the tank.
This topic has been discussed in the past MANY times on this forum.
For example: https://www.clublexus.com/forums/is-...d-threads.html
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Moderator
Joined: Nov 2016
Posts: 9,597
Likes: 4,787
From: GA
Anyway like I said, don't want to get off-topic, as 87 is clearly not recommended for this car.
Pole Position
Joined: Apr 2018
Posts: 2,626
Likes: 459
From: GA
I wish 93 was more widely available here in KC. I know of like two gas stations that have it, and both are BP, both are expensive, and both are out of the way from my normal commute.
Anyway like I said, don't want to get off-topic, as 87 is clearly not recommended for this car.
Anyway like I said, don't want to get off-topic, as 87 is clearly not recommended for this car.
Driver
Joined: Sep 2008
Posts: 158
Likes: 12
From: Germany, Hessen
You won't really get much of a benefit from 93 unless you tuned the car for 93 which our cars are factory tuned for 91. I only use 93 because in Atl and the south in general we only have 93 no 91. Here in Germany, the bases for some reason carry 90 (why not just do 91? lol) and 93 so obviously I go with 93.