What fuel do you run?

What Octane Goes in Your 4R?

  • 87

    Votes: 333 65.7%
  • 89

    Votes: 60 11.8%
  • 91

    Votes: 46 9.1%
  • 91+

    Votes: 63 12.4%
  • 100+

    Votes: 5 1.0%

  • Total voters
    507
87 - not one problem, knock, or performance issue. I stick with Mobil gas as it is consistently the cheapest around me and I know the owner of the station.
 
when I ran 93 it was always 5 bucks more a fill up so thats 1 reason I stopped the premium, 20 bucks a month was an extra tank of gas and I compared numbers and with my driving style I got less mpg with premium
 
'04 V6 LTD 4x4: She's never had 87 since the 1st tank off the lot. I always give her 91 (91 @ Costco; 91 @ Mobil, Shell, Unocal, etc). I used to use Arco, but I've stopped for years now. My dad's friend is a mechanic and he recommends Unocal 76 and advised me to stay away from that gas station mentioned above (just being polite). Besides, I don't like paying a surcharge for the ATM/Debit transaction or using cash to pay for gas even if it's a few cents cheaper per gallon. Credit card transaction is nice because it keeps a tab on my gas expenses for tax purposes. I recently got a Citi card which gives me 5% back (dividend up to $300/yr) which is nice since I drive alot and spend $400-$500 on gas each month.

BTW: as someone mentioned earlier, not all gas stations (of the same name) use the same supplier and the quality will vary. My friend's wife's 325i check engine light came on after a fill up of 91 at a well respected name brand gas station. We happened to drive by one day and saw how much cheaper it was than all the surrounding stations (of the same name). They tried it once, check engine light came on. They took it to the dealer, they found nothing. The light went away after the next fill up. The gas cap wasn't loose either in case you're thinking of that.

One last question & comment, has anyone noticed that there are black soot/carbon buildup (or whatever it is) inside the 4R tailpipe? Mine only has ~15k miles, but there's already a layer of it. My other vehicle ('93 Nissan Quest; used for work) still has the original muffler and the tailpipe is CLEAN, no film/grime on my fingers as I run thru it. Is this normal or abnormal? My mechanic says running 91 reduces exhaust buildup, but I've used all sorts of gas, good & bad, in my Quest. Any inputs? Thx.

Sorry for the long post:D
 
I ALWAYS use premium gas in all my vehicles (93 octane is premium here in GA)...It might be a dollar or two more for a full tank, but I'd rather have better gas and reduce the chance of the ECU pulling timing cuz of knock from lower octane gas.

Better gas means advanced timing which means more power and better efficiency. That is worth the extra dollar or two for a full tank.

I've had premium in my 05 V8 since 3 miles on the odo ;)

Besides...on my 96 Supercharged 4Runner and Supra, premium is REQUIRED

I'm wondering if part of the reason the 03-04 v8 supercharger was pulled was becaus of people putting cheap gas in a supercharged 4runner that NEEDED premium ;) ...cheap gas in a forced induction vehicle = not good..... just a thought
 
Yeah, I guess there's not much you can do if you can't afford to do primium all the time...

But I always wondered.....how can people get $30-$40k automobiles...and try to find the cheap way for everything about it?

I'm NOT bad mouthing anyone so dont take that the wrong way...this is from my Supra thoughts mostly....people spend $30k for a Supra, then say "I can save $20 by using this cheaper piece instead of going with a well-known quality piece" I just dont understand that.

I know it is different with gas...but in my mind...I paid $35k for a brand new vehicle and I will give it nothing but the best.
 
Re: Eh!

hoss said:
91 in the winter it aids in cold weather firing
alternate 87 and 91 in spring and summer and fall

Actually, 87 octane will combust more easily than higher octane stuff.... so you're actually better off with the 87 octane if you're worried about cold weather firing.
 
iFORCE said:
Think about how much money you'll save by using 87 octane rather than 91+? -not much-. So..why not use something better and which also provides a "peace of mind" feeling as well. :D


What makes higher octane better?

If the engine does not knock/ping on 87 octane, than it is equally as good as higher octane fuel.

It is a myth that you'll get higher performance out of 91 octane fuel than you get from 87. The only way that can happen is if the engine knocks on the lower octane fuel and the engine management computer retards the timing to eliminate the knock.... but then again, if the engine is knocking on the low octane fuel, you obviously shouldn't be using it.
 
24runners said:
I ALWAYS use premium gas in all my vehicles (93 octane is premium here in GA)...It might be a dollar or two more for a full tank, but I'd rather have better gas and reduce the chance of the ECU pulling timing cuz of knock from lower octane gas.

Better gas means advanced timing which means more power and better efficiency. That is worth the extra dollar or two for a full tank.

I've had premium in my 05 V8 since 3 miles on the odo ;)

Besides...on my 96 Supercharged 4Runner and Supra, premium is REQUIRED

I'm wondering if part of the reason the 03-04 v8 supercharger was pulled was becaus of people putting cheap gas in a supercharged 4runner that NEEDED premium ;) ...cheap gas in a forced induction vehicle = not good..... just a thought

Right forced induction cars are built to run on higher octane fuel....but your stock Runner was not unless you get a engine managment system to map/ and mod the truck intake/exhaust etc. running high octane does nothing but waste your money....guys this has been beaten to death before, run what your manual says.
 
I used to put premium in my 94 3.slow since day one...and a toy tech at the dealer actually told me to go back to running 87, due to excessive carbon build up from running the higher octane stuff, something about it being slower burning. dunno how true that is, but since then running 87 in both trucks and no probs.
 
Pre-Detonation Resistance

That's all the higher octane fuel gives you. It can be copmressed more before being ignited. Knock and Ping comes from when the fuel is being compressed in the cylinder, BUT ignites before the spark because of compression (compressed gas gets hot). This is why usually only a hot engine will ping or knock. Or a high performance sports car engine. So you have to use higher octane fuels in those motors, to resist pre-detonation.

The modern computers on todays engines detect and eliminate knock and ping. Only the worst kind of garbage fuel will do it. Anyway, that's why if an engine does not specifically require high octane fuel, and it does run fine on lower octane fuel, it's a silly waste of money, there is NO performance benefit when an engine runs fine on either. It's all mental.

This has been known for decades. I still don't know why people insist on tossing money to the oil companies. In fact, they would prefer to make one grade of gasoline, it would solve a lot of delivery and manufacturing costs.
 
Maybe they do distribute one kind of gas... and start adding bottled stuff to the tanks at the gas station to make it a higher octane. :( now.. wouldn't that be funny......
 
Re: Pre-Detonation Resistance

ToolmanJohn said:
That's all the higher octane fuel gives you. It can be copmressed more before being ignited. Knock and Ping comes from when the fuel is being compressed in the cylinder, BUT ignites before the spark because of compression (compressed gas gets hot). This is why usually only a hot engine will ping or knock. Or a high performance sports car engine. So you have to use higher octane fuels in those motors, to resist pre-detonation.

Correct and I agree 100%. Pre-detonation resistance is worth a few dollars to me ;)


The modern computers on todays engines detect and eliminate knock and ping. ...

And the ECU eliminates knock and ping how...??? By pulling timing.... = less performance. And if you ever do knock...the ecu pulls timing and gradually gives it back over time (maybe enough time to let you get into another tank of gas).

Also, (especially with our VVT-i on the 95's) most ecu's (not sure about the 4Runner) will advance the timing with better gas. Also, technically, lesser octane gas will produce higher egt's...maybe not a whole lot, but it does ;)

I do agree that the only other benifit that seems to come from using higher octane gas (besides running advanced timing for better performance/efficiency) is IF you come into a situation where the lower gas would cause knock. This may not happen often...or even at all....but my extra $2 at the pump will, in my head, give me a little more protection against pre-detonation.

Again...I am not bad mouthing anyone that uses 87...I'm just trying to explain why I choose the 93. As always...to each his/her own :) but I say, bring on the 93 octane and advance my timing *hehe*
 
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02sport said:
I used to put premium in my 94 3.slow since day one...and a toy tech at the dealer actually told me to go back to running 87, due to excessive carbon build up from running the higher octane stuff, something about it being slower burning. dunno how true that is, but since then running 87 in both trucks and no probs.

True, lower octane gas does burn hotter, therefore reducing the potential carbon buildup.

However, If you drive like a grandma and NEVER floor it (wide open throttle) you might have carbon buildup (and by all means, please use 87). If you pass someone at least once a month, you "blow out the carbon buildup". I don't drive like a grandma.

And you probably will not have any problems running 87...I'm just sayin that there are benifits to using 91 or higher. its up to you to decide if its worth the extra cost

Also, TOYOTA RECOMMENDS at least 91 octane...I wonder why ;)
"Test AWD V8 Sport averaged 15.5 mpg. No opportunity yet to measure with V6. Toyota recommends 91-octane premium fuel for both engines."

http://auto.consumerguide.com/auto/new/reviews/full/index.cfm/id/23334.htm

Even Boating Magazine says premium is recommended for both engines.

FROM MY 2005 TOYOTA OWNER'S MANUAL:
"For improved vehicle performance,the use of premium unleaded gasoline with an Octane rating of 91 or higher is recommended." -- page 282

pressroom.toyota.com recommends 91:
http://pressroom.toyota.com/photo_library/display_release.html?id=2003gx470_s

So......I'm using the high octane ;)

Bty, the Lexus people (4Runner brother) are having the same argument on their site *LOL*
Here's the Lexus fuel debate

My favorite quote:
"You will spend $200-300 a year more for better fuel and we are talking about $50,000-$70,000 cars....And your worried about a couple of hundred dollars a year?"
 
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24runners said:


However, If you drive like a grandma and NEVER floor it (wide open throttle) you might have carbon buildup (and by all means, please use 87). If you pass someone at least once a month, you "blow out the carbon buildup". I don't drive like a grandma.




haha, if you've ever driven a 3.slow, you'd know you're constantly driving at WOT:D the slightest grade change in the highway and your back to flooring it to keep up with the flow of traffic.:) makes me wish i could've had a V8 :D
 
Re: Re: Pre-Detonation Resistance

24runners said:


And the ECU eliminates knock and ping how...??? By pulling timing.... = less performance. And if you ever do knock...the ecu pulls timing and gradually gives it back over time (maybe enough time to let you get into another tank of gas).

That's not really how it works. Yes, the knock sensors will cause the timing to immediately retard upon sensing knock. In fact, the timing is retarded in small steps, typically just one or two degrees at a time. The knock sensors contstantly moniter for knock/ping and only adjust the timing from the factory set point upon detecting knock. In other words, the only time the timing will be retarded is when the engine is actually knocking. Then it will return to the original set point.

Also, (especially with our VVT-i on the 95's) most ecu's (not sure about the 4Runner) will advance the timing with better gas. Also, technically, lesser octane gas will produce higher egt's...maybe not a whole lot, but it does ;)

No factory engine management system (that I'm aware of) will advance timing beyond the original set point, regardless of the gas you're running. The way it works is that the engineers determine where the timing should be and that is where it stays. As already discussed, the timing can be retarded to eliminate the possibility of knock, but it cannot be advanced by an engine management system. If it could, you'd see every Tom, Dick and Harry running Cam II in their little sportscars.

As for exhaust gas temps.... octane has absolutely no effect. This is a well-documented and proven fact.
 
I never said that it would advance the timing past any point...its obviously not going to keep advancing the timing infinitely.....I am comparing the timing using 87 and using 93...simply saying that with cheap gas, you have more of a chance that your ecu is pulling timing.....maybe it is...maybe it isnt...I havent monitored knock in this 4Runner yet....I'll spend the extra $2 and know I'm doing the best I can to help the ecu keep my timing where it is

There is a reason toyota recommends 91 or higher octane....and I'll be willing to bet it is because of the timing and performance issue. Am I the only one with that in my owner's manual???

I will use my laptop to monitor my timing advance and retard....the next tank of gas I will only put in about a quarter tank of 87..let it run for about 40/50 miles on that...then monitor the timing and knock....we'll see if the timiing is affected by the cheaper gas ;)
 
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