amf1932

So far I have been using 91 or 93 octane on this '07 ES, but I will continue to drop the octane rating on future fill ups towards 87 and see if the performance or gas mileage suffers.
I have done this on my previous ES's('90, '94, '03) to get the best all around economy.......and I've always found that 87 octane works best for my uses.

Kaius88

I might try a tank of 87 octane and see if it makes a difference. I highly doubt changing grade would mess things up.

Here's my only complaint: I dont understand why my MPG is around 19 - 20 on local streets, and I average 33 MPG easily on the freeway... That's a huge gap. I'm complaining because my commute everyday is 80% local, so the fuel economy doesnt really benefit my situation. So i guess the fuel efficiency is ONLY applicable at high speeds....

amf1932

That's the name of the game. What ruins your fuel economy is the constant shifting and braking in city traffic. I doubt whether your mileage will suffer if you use 87 octane. In all my previous Lexus cars I never noticed any difference, or if there was, it was miniscule.

Pheonix

Sitting still, and accellerating with your foot bearly on the pedal kills gas mileage. You're running the engine at a poor volumetric effecciency , just like most gasoline engine at those speeds. (I calculate it at 80-85% VE. (Which keep in mind. Is phenominal at that rpm range.) And that's at wide open throttle. The more the throttle plate closes, the loss goes through the roof.
The torque convertor never gets to stay locked up for long periods of time.
More parasidic loss from the cooling system.

I'm sorry to be the bearer of bad news Kaius88, but that's simply how every gasoline engine works. You're using the engine in it's worst application range driving it in the city. Unforetunately, every gas engines works that way. It's nothing new to scoff about!



Gas tank addatives are a joke. They don't clean injectors on these cars & the injectors are almost unheard of to dirty to a clog to begin with. They generally overheat & stick open, or the spring finally wears out past the point that the ECU can no longer control the mixture accureately enough with it. The fuel system is doubled filtered, has been for 20 years. Nor do gas tank addatives contain enough of anything, in the extremely diluted mixture in the gas tank, to do anything constructive to the internals of the engine. It's not going to bust carbon out of the combustion chambers at the recommended 1008:1 ratio (2.0625oz per 10 gallons of fuel)
Oil treatement, chunking a ton in the intake. Sure, that works. Always has.
It's going to raise the octane very slightly.

FYI.
Lexi/Toyota dealers use Toyota brake cleaner, Toyota throttle body cleaner to service an injector when it's off of the car, or do any other mechanical cleaning on the car. Most also do buy FP60. The differance, is when they do actually use the FP60, it's either to remove suspected moisture in the gas tank, or as a solevant in a machine that bolts to the fuel rail that does not dilute the mixture as much. (i.e. motorvac type machine) Because it works better than the Toyota specified injector cleaner.


amf1932, we've all talked about octane before. You're on it exactly. You already know this, but for everyone else, the lower the octane, the more energy the gas has, the more potential power you can make off it, and the lower the emessions. Provided the engine doesn't experiance pre-ignition.
If the engine isn't using the knock sensors to pull ignition timing in an attempt to avoid detonation, It's golden gas. But you already know all of that.

Kaius88

That's way too advanced of a level for me to fully comprehend. Pheonix are you a mechanic or an extreme car enthusiast?

dshahs420

Another good idea if you want better gas mileage is to NEVER use the Drive-thru window at any restuarants, coffee shops and such. I can care less so i do use drive-thru's but just FYI's for people.