Just filled up the tank with 91 octane premium fuel - Page 5 - Toyota Yaris Forums

Yaris Hilton · 05-14-2009, 12:57 PM

You're looking at Research Octane Number. It's established in a special low speed engine with cold air intake and a low operating temperature. There's also a Motor Octane Number that's much more reflective of fuel performance in real world automotive engines, but it's a considerably lower number. When the US required posting of octane numbers at the pump, the various involved parties couldn't agree on which number to post, so they compromised on the average of the two, R+M/2. It's actually a meaningless number as the "sensitivity" or difference between the two numbers can vary substantially, so one "87 pump octane" gasoline may knock more easily than another.

liyux2k · 05-28-2009, 06:23 PM

the engine is already running at max specs with 87. what ever better fuel you put in just going to force the engine to wear more in order to burn it since the compression stays the same. is not going to boost performance or mileage, the only thing it does is more wear towards the engine. ;)

SilverGlow · 05-28-2009, 09:12 PM

Only idiots put high octane gas in a itty bitty Yaris motor...they say they "feel" the difference...all BS....higher octane means higher flashpoint, meaning LESS POWER, LESS TORQUE, LESS MPG...LESS CLEAN COMBUSTION....

Leave the 91 octane to motors truly need it like high compression engines, turbo engines, super charged, many BIG displacement engines, etc....only boy racers with one foot still in the sand box swear by 91 octane....all that money wasted...it adds up after years of stupidity....

schleppy · 05-29-2009, 02:45 PM

87 octane is the lowest recommended isn't it? I wouldn't go lower than that, esp. at higher altitudes.

Forrest · 05-30-2009, 08:17 AM

With the cost of gas going up so quickly, yesterday, May 29th it was 2.60 for 87 and 3.00 for highest oct., I would stick to the recommended gas at the lower price.

borezack · 05-30-2009, 09:27 AM

OK thanks for the info

Yaris Hilton · 05-30-2009, 02:42 PM

How far you go on the first bar depends heavily on how full you fill the tank. I run the pump fast till it clicks off, wait a few seconds, start it back at a trickle and let it click off again. (It barely puts in a dollop of gas the second time, but it makes for a pretty consistent fill without overfilling.) I usually get close to 100 miles on the first bar.

ImportRacer88 · 05-30-2009, 09:27 AM

when i first got mine i ran preimum once and the car ran like shittocky mushrooms and when i went to fill up i put regular back in it and it ran better so i just been running reg had no probs here but im moving back to pa has ne one had any probs woth thier CAI in the snow pm me and let me know

voodoo22 · 05-31-2009, 07:19 PM

We've never put in anything other than 87 octane. We purchased the Yaris to reduce travel expenses and given it's performance over the first 79 fill ups 87 octane suits it quite well.

We do only fill at top tier stations though.

Thai_Dang · 07-01-2010, 05:15 AM

91 octane will make your penis larger. yeah i've also read anything above 87 is harmful for your engine. Makes sense, these cars have sensitive timings. But i can't imagine with how many computer chips they put into these cars nowadays, that the ECU would detect the 91 octane that some idiot put in their car and adjusted the timings of fuel injection so it doesn't cause engine knock/build-up.

ddongbap · 07-01-2010, 07:03 AM

HOLY THREAD REVIVAL.

yarrr · 07-12-2010, 10:01 PM

Quote:

Originally Posted by ddongbap

HOLY THREAD REVIVAL.

ya its kind of his thing if you hadn't noticed. I think maybe his "new posts" button reads "old posts" and he can only see the oldest posts on the forum.

10peep · 03-21-2011, 09:54 PM

Quote:

Originally Posted by ddongbap

HOLY THREAD REVIVAL.

I just spent 35 minutes reading this pissing contest so I absolutely HAVE to make some kind of comment to revive it. You ready....? Here it is.........comment.

Quote:

Originally Posted by 07WYarisRS

"......Thats why many bio deisel set up have a deisel start because the biomixtures like used engine oil of veggie oil often has a much higher flashpoint and is harder for the engines to start on them. they start on the diesel and then switch over to run on bio once warmed up......."

^^^ This is wrong, btw. Biodiesel setups usually do not have any type of diesel start or diesel purge setup because biodiesel is made by the user from WVO. On the contrary, WMO/WVO setups almost always have a diesel start and diesel purge setup because the viscosity of the "fuel" (WMO/WVO) is MUCH higher than the viscosity of ordinary diesel until it reaches temperature (usually around 180deg) and will very quickly clog up one's entire fuel system if initiated before it reaches optimum temp. Consider this thread revived and maybe now we can discuss something MUCH cooler than octane ratings, smoothness and high/low compression engines....DIESEL!!!!

frog13 · 07-12-2010, 09:51 PM

Compression dictates octane

Idahotom · 03-21-2011, 11:23 PM

Speaking of diesel: I was at a gas station in SE Idaho the other day, fueling up my 22 ton boom truck. I was astonded to see they were offering straight diesel ($3.86 per gallon), off road/non dyed (and you do NOT want to get caught with that in your tank) for $3.64, and lastly bio diesel for $3.86. The owner of the station must be a diesel freak! As everywhere else was elling diesel for $3.97 or higher, I was a happy camper.

A few days earlier, while also fueling the boom truck, I struck up a conversation with a VW Jetta driver: 47 to 49 MPG, and he had over, well over, 200,000 miles on it. Without even doing the math (in general higher priced diesel V. gasoline) the Yaris compares well...( in the low 40's, my own results) plus I trust Toyota more then VW!

10peep · 03-22-2011, 09:25 PM

Quote:

Originally Posted by Idahotom

Speaking of diesel: I was at a gas station in SE Idaho the other day, fueling up my 22 ton boom truck. I was astonded to see they were offering straight diesel ($3.86 per gallon), off road/non dyed (and you do NOT want to get caught with that in your tank) for $3.64, and lastly bio diesel for $3.86. The owner of the station must be a diesel freak! As everywhere else was elling diesel for $3.97 or higher, I was a happy camper.

A few days earlier, while also fueling the boom truck, I struck up a conversation with a VW Jetta driver: 47 to 49 MPG, and he had over, well over, 200,000 miles on it. Without even doing the math (in general higher priced diesel V. gasoline) the Yaris compares well...( in the low 40's, my own results) plus I trust Toyota more then VW!

NICE!!! Yeah, its hard to even FIND off road Diesel here in VA, much less without any dye in it. Its SO funny you mention a VW diesel... I was ON MY WAY to the stealership to BUY a VW diesel that I had ALREADY test driven a couple days earlier but I had read SO many bad things about EVERYTHING other than the motors on these cars that I just didnt feel comfortable doing it. I figured that Id swing by the local Carmax to see what they had first walked right PAST the Yaris that I actually ended up going back and buying 4 days later. Went across the street to the VW, Subaru place and some guy came in with a diesel Jetta and couldnt say enough about how much of a turd it was and thats all it took for me. Went across the street to the Toyota joint, test drove a new Yaris (on my wife's suggestion, because she saw the one at Carmax

), went back to Carmax and bought mine for $5k off of sticker with 12k miles on it.

The Spectacle · 08-20-2011, 12:36 AM

I'm digging this up from the dead rather than creating my own thread because I'm sure it would just spiral down the same road.

I've just filled up my tank with 89 after 3 years of nothing but the 87 and there is DEFINITELY a difference in throttle response and midrange power. I'm still a bit shocked myself but its there.

I read through a few of these responses and its clear that not many of you know how knock sensors and timing retard/advance work. That's all well and good but I just want to state for the record that Yaris behaves slightly different if you put higher octane in it.

ROCKLAND TOYOTA · 08-20-2011, 10:40 AM

Quote:

Originally Posted by The Spectacle

I'm digging this up from the dead rather than creating my own thread because I'm sure it would just spiral down the same road.

I've just filled up my tank with 89 after 3 years of nothing but the 87 and there is DEFINITELY a difference in throttle response and midrange power. I'm still a bit shocked myself but its there.

I read through a few of this responses and its clear that not many of you know how knock sensors and timing retard/advance work. That's all well and good but I just want to state for the record that Yaris behaves slightly different if you put higher octane in it.

im SHOCKED it took you 3 years to fill up with something else!!!

WELCOME to the club and when you get to the last few bars on the guage you'll notice they don't disappear as fast.....

05-30-2009, 09:27 AM	#8
ImportRacer88 View User's Garage Drives: 4dr Sedan s Join Date: Nov 2008 Location: Meshoppen, Pa 18630 Posts: 86	when i first got mine i ran preimum once and the car ran like shittocky mushrooms and when i went to fill up i put regular back in it and it ran better so i just been running reg had no probs here but im moving back to pa has ne one had any probs woth thier CAI in the snow pm me and let me know __________________

08-20-2011, 12:36 AM	#17
The Spectacle View User's Garage Drives: 08 BSP LB Join Date: Oct 2008 Location: Tampa, FL Posts: 218	I'm digging this up from the dead rather than creating my own thread because I'm sure it would just spiral down the same road. I've just filled up my tank with 89 after 3 years of nothing but the 87 and there is DEFINITELY a difference in throttle response and midrange power. I'm still a bit shocked myself but its there. I read through a few of these responses and its clear that not many of you know how knock sensors and timing retard/advance work. That's all well and good but I just want to state for the record that Yaris behaves slightly different if you put higher octane in it. __________________ Last edited by The Spectacle; 08-20-2011 at 12:56 PM.

Thread Tools
Show Printable Version Email this Page
Display Modes
Switch to Linear Mode Hybrid Mode Switch to Threaded Mode

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Fuel Efficiency and the Yaris	BailOut	Fuel Economy Forum	327	Yesterday 12:44 AM
Fuel Economy	swng	Fuel Economy Forum	2089	01-23-2015 07:41 PM
Yaris Fuel Pump	HTM Yaris	General Yaris / Vitz Discussion	12	03-22-2012 04:34 AM
Last Fuel Bar	andaconda	Fuel Economy Forum	37	04-29-2009 03:35 PM
The Advantages of Nitrous on an Engine	KCALB SIRAY	Performance Modifications	7	01-02-2009 11:53 AM

05-14-2009, 12:57 PM	#1
Yaris Hilton Half a Bubble Off Plumb Drives: 2009 Yaris Sedan Join Date: Mar 2009 Location: Bristol, Tennessee, USA Posts: 1,593	You're looking at Research Octane Number. It's established in a special low speed engine with cold air intake and a low operating temperature. There's also a Motor Octane Number that's much more reflective of fuel performance in real world automotive engines, but it's a considerably lower number. When the US required posting of octane numbers at the pump, the various involved parties couldn't agree on which number to post, so they compromised on the average of the two, R+M/2. It's actually a meaningless number as the "sensitivity" or difference between the two numbers can vary substantially, so one "87 pump octane" gasoline may knock more easily than another.

05-28-2009, 06:23 PM	#2
liyux2k Drives: Vios Join Date: May 2009 Location: Hong Kong Posts: 8	the engine is already running at max specs with 87. what ever better fuel you put in just going to force the engine to wear more in order to burn it since the compression stays the same. is not going to boost performance or mileage, the only thing it does is more wear towards the engine. ;)

05-28-2009, 09:12 PM	#3
SilverGlow Banned Drives: 2007 Yaris Hatchback Join Date: Oct 2008 Location: Southern California Posts: 189	Only idiots put high octane gas in a itty bitty Yaris motor...they say they "feel" the difference...all BS....higher octane means higher flashpoint, meaning LESS POWER, LESS TORQUE, LESS MPG...LESS CLEAN COMBUSTION.... Leave the 91 octane to motors truly need it like high compression engines, turbo engines, super charged, many BIG displacement engines, etc....only boy racers with one foot still in the sand box swear by 91 octane....all that money wasted...it adds up after years of stupidity....

05-29-2009, 02:45 PM	#4
schleppy I love momentum. View User's Garage Drives: 2009 Yaris LB, Red Join Date: Feb 2009 Location: Boston, MA Posts: 587	87 octane is the lowest recommended isn't it? I wouldn't go lower than that, esp. at higher altitudes.

05-30-2009, 08:17 AM	#5
Forrest Drives: 08 LB BLACK Join Date: Oct 2008 Location: NY Posts: 244	With the cost of gas going up so quickly, yesterday, May 29th it was 2.60 for 87 and 3.00 for highest oct., I would stick to the recommended gas at the lower price.

05-30-2009, 09:27 AM	#6
borezack Drives: 08 Yaris Sedan Join Date: May 2009 Location: Ut Posts: 3	OK thanks for the info

05-30-2009, 02:42 PM	#7
Yaris Hilton Half a Bubble Off Plumb Drives: 2009 Yaris Sedan Join Date: Mar 2009 Location: Bristol, Tennessee, USA Posts: 1,593	How far you go on the first bar depends heavily on how full you fill the tank. I run the pump fast till it clicks off, wait a few seconds, start it back at a trickle and let it click off again. (It barely puts in a dollop of gas the second time, but it makes for a pretty consistent fill without overfilling.) I usually get close to 100 miles on the first bar.

05-31-2009, 07:19 PM	#9
voodoo22 Drives: Yaris Sedan (auto) Join Date: Jun 2007 Location: Toronto, Ontario Posts: 545	We've never put in anything other than 87 octane. We purchased the Yaris to reduce travel expenses and given it's performance over the first 79 fill ups 87 octane suits it quite well. We do only fill at top tier stations though.

07-01-2010, 05:15 AM	#10
Thai_Dang View User's Garage Drives: 2010 Yaris 5-Door LB AT MM Join Date: Jun 2010 Location: Los Angeles Posts: 57	91 octane will make your penis larger. yeah i've also read anything above 87 is harmful for your engine. Makes sense, these cars have sensitive timings. But i can't imagine with how many computer chips they put into these cars nowadays, that the ECU would detect the 91 octane that some idiot put in their car and adjusted the timings of fuel injection so it doesn't cause engine knock/build-up.

07-01-2010, 07:03 AM	#11
ddongbap Banned Drives: yw calls me douche and racist. Join Date: Aug 2007 Location: hay Posts: 2,183	HOLY THREAD REVIVAL.

07-12-2010, 09:51 PM	#14
frog13 Tw200--excellent! Drives: 2010 yaris..absolutely red. Join Date: Jun 2010 Location: Ohio Posts: 210	Compression dictates octane

03-21-2011, 11:23 PM	#15
Idahotom Drives: 2008 5 sp. LB Join Date: Oct 2010 Location: Idahoi Posts: 268	Speaking of diesel: I was at a gas station in SE Idaho the other day, fueling up my 22 ton boom truck. I was astonded to see they were offering straight diesel ($3.86 per gallon), off road/non dyed (and you do NOT want to get caught with that in your tank) for $3.64, and lastly bio diesel for $3.86. The owner of the station must be a diesel freak! As everywhere else was elling diesel for $3.97 or higher, I was a happy camper. A few days earlier, while also fueling the boom truck, I struck up a conversation with a VW Jetta driver: 47 to 49 MPG, and he had over, well over, 200,000 miles on it. Without even doing the math (in general higher priced diesel V. gasoline) the Yaris compares well...( in the low 40's, my own results) plus I trust Toyota more then VW!