kzoosho

iTrader: (16)

U . Try 5.49 a gallon.

redmaxpa007

iTrader: (21)

3.05 for premium here in western Ga

kzoosho

iTrader: (16)

Yea i dont run premium . I use race fuel.

MacGarnicle

iTrader: (1)

There are a lot of reasons to use premium aside from "gas mileage"... I'm not sure when that became a leading reason to use premium

Knock sensor makes sure the car decently on less than premium, but that doesn't mean you're doing the car any favours necessarily. At the end of the day, most people seem to be able to get away with lower octane fuel, so it comes a preference. Me, I'll stick with what's recommended: premium.

Deven2kStickMax

you will be just fine. go even 87. remember these cars were all made to run on unleaded gas, premium gas is more for performance. You will save $$$, just don't by from crappy gas stations like Getty, go for Shell, BP etc...

95arcticpearl

iTrader: (3)

i have a 95 se which in the manual reccomends 91 for the best performance...i was running 89 for a while because of the gas prices and kept having an o2 sensor code pop up...i switched to 91 just recently and that code has yet to come back...i dont know if it's just a coincidence or if the higher octane helped the problem

Deven2kStickMax

have your ever changed your 02 sensors? if not try changing them, then go back to 89 and you should be fine, unless the light comes on for something else. where did you had your check engine light checked? hope it was not autozone b/c their reading compare to the dealer one is different.

Deven2kStickMax

we have the same car. it didn't recommend premium, it says for maximum performance use premium, otherwise the car was built to run on unleaded gas....

bigjoe87865

iTrader: (1)

jebus...

i didnt think it costed that much anywhere in the US... thats like european/asian prices

bigjoe87865

iTrader: (1)

Anyways.... i put in 20$ of 89 octane this morning... about 5.6 gallons i think... ill have to double check.... almost ran the tank dry before putting it in... DTE was showing --- and was driving for 15 miles in the city since it started showing ---


anyways...it didnt knock or ping.... my DTE shows lower miles than what its supposed to be... instead of 165miles... it showed like 150... BUT my MPG guage... just started seeing 2mpg higher...


i know not to rely on that computer at all... im just stating what i saw..


anyways... the needle seems to be moving a bit faster to empty than 93 octane...


lets see.

Deven2kStickMax

i had a 2004 and i use regular before. the computer will adjust. most of the time it lies anyway. you are doing fine....

kzoosho

iTrader: (16)

Yea it does. Sunoco 100 octane is 5.49 a gallon i know this since i use it .

LJ2Blessed

Interesting...I'm glad I kept glancing at this thread. I've been using 92 at Speedway/SuperAmerica but live close to a Shell now. I'm going to try their midgrade to start, and see how that goes. New Nissan dealership in my area too, so as my budget allows everything will be finely tuned...

Thanks for the info!

nk2k2

iTrader: (7)

Shell V-Power all the way. Shell sold me on V-power and ive been using them ONLY since i bought the max. I use 93 every fill up regardless of price. Right now in Northern VA, its about 3.15 for V-Power at the pump. I dont like to switch around on different gas companies. Since ive had the car, its only had v-power in it. It runs smooth, no pinging or any problems. I average about 21-22 mpg city with my 3.5 auto. Not bad considering i have a heavy foot here and there plus its a V6.

bigjoe87865

iTrader: (1)

Welll did 5.9 gallons of 89 octane.... and got 133miles... till the DTE went --- and the gas guage was pretty much near the needle stop... (about 14miles after ---- )

^ i did this at Mobil gas station...

now i pumped up 5.9 gallons at Shelll @ 87 octane..... and the needle is a bit higher than the mobile fill up... even though its almost the same amount....give or take half a gallon.

ramberg

iTrader: (29)

I only use premium gas in my car and regular in my wife's car. Its $3.53 a gallon for premium in Brooklyn, NY.

carsarecool

iTrader: (1)

Yea I've been paying 3.47-3.55 in upstate ny for premium, I'm jealous of you guys that have Shell's near you, theres maybe 1 within 80 miles of me, or having to travel out of state. We've got Citgo, Sunoco, Hess and Mobil...I usually get Hess 93 and was gonna say we dont even have any Top Tier gas around here but Mobil is isnt it? or no?

JimPark

Well, I have a 93 SE and I used to use premium for the first 10 years but have since switched to regular. It probably helped the engine during those 10 years but I haven't noticed that much of a difference since changing and, to be honest, after 14 years I started caring a little less.

Prophecy99

iTrader: (1)

Would the saveing in gas consumption make up for the upped $.20-.30 per gallon?

What are some mileage #'s using premium vs reg....
I am open to using premium...but reg around $3.01...has been totally fine...

leefitz

In the Phoenix area the highest octane available is 91. I use only Chevron 91 in all my cars.

hondadude

$3.19 here for premium, I figure if that is what Nissan feels the car should have, that is what I am going to put in it. It only cost me an extra $3.00 or so to fill up each time, so I see that as not a great price to pay.

92ZexMaximaSE

Using E85 here--- 100 octane.. ha ha.. not for my Max, but for my Titan. It's about .40 cheaper than regular gas. People complain and gripe about poorer gas mileage running E85 but so far after 3 tankfuls, I have only seen a very slight decrease in gas mileage. When I had my Maxima, plain unleaded for me. Saw no use for using premium even with mods..

lightonthehill

Prophecy99 -

I realize this thread has gotten way too long to expect anyone to read through every post, but the truth that carefully controlled lab tests have shown, the truth that many drivers have always known, and the truth one can find in this thread given a lot of time to read through it, is that:

************************************************** ************************************************** ************************************************** ************************************************** ****


IN A PROPERLY TUNED CAR, OCTANE HAS ABSOLUTELY NO EFFECT ON GAS MILEAGE, urban rumors notwithstanding.


************************************************** ************************************************** ************************************************** ************************************************** ****

People only use higher octanes because:

Nissan, while telling us very clearly that the car runs fine on 87 octane, recommends higher octane because the higher octane might improve engine cleanliness slightly, and could give a little performance boost during extreme maneuvers, such as a timed quarter mile. Nissan also realizes that people are suggestible, and that many folks associate the manufacturer's recommendation of higher octane as being a hint of a car's higher performance capability, and that can't hurt Maxima sales.

OR

They believe the untrue rumors of higher mpg with higher octane that eminate from misguided and poorly run and improperly controlled 'road tests' from drivers who don't want to feel they are spending bigger bucks and not getting greater mpg.

OR

Their car is slightly out of tune, or has some other problem that can be masked by using higher octane.

OR

They just want the best for their Maxima, because they understand they are driving a very special vehicle.



But higher mpg with higher octane? In a properly tuned car, there is NO CONNECTION between these two numbers.

LvR

Amen brother!

People are quick to crap allover one for posting facts and putting up arguments to counter posted fallacies, yet they have absolutely no willingness to debate the garbage they sprout so liberally.

As I suggested right in the beginning of this thread (also remembering that this thread actually started on the 3rd gen forum) - go and read my comment on octane and its affects on worn motors I linked to.

Its as simple as this:

The engine's mechanical design is fixed no matter what you do as owner to the vehicle ito tuning - as such, its efficiency is fixed if its operating at the correct tuning parameters for the fuel you feed it. Any normal fuel you can buy at a pump on the road, of any octane rating you feed the motor, contains the same base fuel volume - different octane fuels get "produced" by adding additives in an absolute minute percentage per volume (and this is only talking the same brand of fuel!).

Because there is the same base fuel volume, the exact same amount of stored energy is available for any given octane fuel per volume, and if its ignited and burnt in such a way that you extract the maximum amount of energy from the fuel based on your engine's limitations, there can be no direct correlation between the octane and fuel efficiency.

Yes - you can have additives affecting the energy content of fuels, but in the minuscule small quantities of additives present, the effect is for practicable purposes not measurable in a typical vehicle in real world and uncontrolled driving conditions - on top of that additives can have either positive or negative influences on fuel energy content, so any poster saying there is a measurable difference without specifying brand of fuel (let alone all the other factors involved) is living in lala land ...................

Typical recent example:

"give or take half a gallon. " VS "and the gas gauge was pretty much near the needle stop... (about 14miles after ---- )" ......................... now in any fuel consumption calculation/evaluation those terms are definitely an oxymoron

bigjoe87865

iTrader: (1)

lol... yes that was me..... and i very well knew that those words arent supposed to be taken scientificlly at all... what so ever..... it was just a simple quick cheap personal test for my satisfaction... and wanted to post what i saw....

kvg

I use premium in mine gives me better mileage and more power. if i use regular then it actually costs more because my mileage drops.

bigjoe87865

iTrader: (1)

Ok... i tried searching around...


is the vq35de motor a high compression motor?... that requires the higher octane to prevent the premature detonation that i keep reading about?...

i dont care about KS or anything.... i just finished reading about 3 threads... and came down to the conclusion..

Premium fuel... is there to prevent the pre igniting in higher compression motors.... because premium fuel ignites at a higher temp.... giving high compression motors "breathing room" during compression...


so yea... is the VQ a high compression motor?

LvR

Premium or higher octane fuel is available for use in motors with higher compression ratio designs - higher octane fuel resists spontaneous ignition/combustion because of too high a pressure being present in the combustion chamber given other parameters (temp and mixture quality) stays the same.

Car designers are forever out to extract as much power from their engines as possible - one easy way is to increase compression ratio as internal combustion engine efficiency increases with increases pressure (and as a result of that temp). You may not care about the KS as per you comment, but most modern ECUs are using the KS to dynamically set the engine ignition timing by detecting the presence of knock and keeping ignition timing to occur at a point just before the onset of knock - completely irrespective of the octane rating of fuel used .................. the result? - sure the motor may/will feel like crap but it will run on any reasonable octane fuel you feed it

If you read that link in my first post again, you will see that engine manufacturers strive to get the point of controlled combustion and maximum cylinder pressure as close as possible to around 15 ATDC to ensure maximum efficiency of the use of the burnt fuel's energy (maximum torque extracted from every power stroke of the motor) and they will usually tell you in the owners manual what they recommend ito of octane requirements for the motor to get the optimum performance from it.

If you choose to drive on something other than that, your motor may be down on power on each and every power stroke of the motor irrespective of the way you drive ..................... if you improve your actual fuel consumption measurement techniques , you will be able to prove on your own motor, in its current state of wear and tune, with the specific brand/quality of fuel, and under your specific driving conditions, whether the higher octane fuel is going to offer a measurable and useful return on your use of more expensive fuel (compared to a lower octane fuel).


General comment to all people here trying to make this issue a real simple higher octane is always better thing:

Go read my first post's link again and then understand that once you are able to affect/guarantee ignition in your motor so that the max pressure occurs around 15 ATDC with eg 87 fuel and a given state of tune, you simply cannot get anything more/better out of that motor of yours ................. you are already at the point of maximum efficiency ................... you simply cannot get more mpg out of that vehicle by changing to a different octane rated fuel - either higher or lower than the 87 I used in the example above.

Deven2kStickMax

let's put this thread to a rest people....all MAXIMAS were made to run regular gas. higher octane is throwing money into and out the tail pipe. can we all settle on regular and keep the engine clean? As lightonthehill says above, "IN A PROPERLY TUNED CAR, OCTANE HAS ABSOLUTELY NO EFFECT ON GAS MILEAGE, urban rumors notwithstanding"

bigjoe87865

iTrader: (1)

ok i read the post and the previous link.... and i feel like you basicly went into to detail what i already said in my previous post...

higher compression = more pressure = pre ignition = knock , ping...
(and age and mileage of motor can add to it... ) = the KS sensors will retard the timing = prevention of preignition , knock , ping = less power being put out

and higher octane = higher temperature for combustion = less of a chance of pre ignition = less knock ping...

---

i still didnt get the answer to ...whether.. the vq35de is a high compression motor or not...

and iv put in a full tank of 87 right now..... i hear no knocks... no pings....the car feels fine.... but how do i know if the KS sensors are retarding the timing and preventing the knocks and pings and giving me less power... hence less mpg?

Nopike

iTrader: (2)

I previously used 93 octane but the better I understand the subject the less I am inclinded to use 93. If you read many of the articles on the subject you will learn that the higher octane value only delays inginition of the fuel. Preignition should only be an issue under high pressures and temperatures that are experienced under heavy load. If I were towing or racing or it was a very hot day I may use the 93 octane fuel. For normal driving (95% of the time) it is a waste of money. As far as the octane of the fuel ruining your knock sensor I don't understand that logic. The knock sensor is only there to "listen" for engine knock, the fact that it "hears" engine knocking or not should have no bearing on its ablity to function or it's longevity.

bigjoe87865

iTrader: (1)

exactly what i seem to understand from all my reading... even the part about the knock sensor..... using low octane isnt ruining the sensor... its a design flaw that is...

but is the vq a high pressure engine?...

LvR

I know I will most likely get flamed for this but here goes anyway:

No - it better resists spontaneous combustion at higher pressures - the higher the octane value the more resistant the fuel is to pressure values causing spontaneous/uncontrolled/unwanted combustion - the higher the octane value, the bigger the window is within which you have precise control over the creation of a reliable and predictable maximum pressure wave on the pressure stroke of the motorAgreed...............
Your owners manual tells you what the compression ratio is on your particular vehicle - my guess is its higher than my VG motor's thoughYou missed the point most of us trying to go into detail here is making:

If you have the same base fuel and thus the same basic energy content per volume of fuel for 2 different octane rated fuels, then as long as you ensure the max pressure to occur on the power stroke of the motor at the correct time for any octane rating of fuel you use, there will be no knock/ping and the efficiency of the motor is not affecting mpg AT ALL ........................... the mere fact that you run on 87 ISO any other higher octane rating does not automatically guarantee the retarding of timing - its a function of whether or not the motor will knock with that lower octane fuel ISO higher or recommended stuff - if it doesn't immediately knock on seeing 87, then nothing is going to happen ito timing and the motor will simply continue to run as with the higher octane fuel and your experience will be as per you description - effectively no change experienced and hence Deven2kStickMax last comment when looking at any given modern KS base, ECU controlled motor.

There is no simple way of detecting that the KS is retarding timing because of too low an octane fuel being used other than with either a dyno or a long term fuel usage measurement - its a huge function of the specific engine and the specific driving conditions as I said before.No - not so - higher engine temps/inlet temps usually results in moving the ignition characteristics closer to a state of pre-ignition ie making things way more critical

bigjoe87865

iTrader: (1)

thanks for going into detail with me... im a bit stubborn ... thats all..

still not a 100% understanding everything..... but ill take ur word on it....

as long as i didnt hear knocking or pinging when my motor took in 87.... its probably not being retarted by the KS right?...

and if i ever get a chance on the dyno.... i should do one run with 87... and one run with 93... and if the 93 is giving higher numbers... it means the KS is retarding the timing on 87 to prevent knocking?

LvR

Wrong conclusion. It may indeed be the case, but there is no way of knowing what exactly is happening unless you investigate in detail - if you, as the person frequently driving the car, cannot feel/hear a difference I would say forget about it all.Again - Wrong conclusion. It may indeed be the case if the dyno tests are done very systematically and in a very controlled manner, but the preparation of the vehicle, environment, ECU adaptation period with the differing fuels etc etc all play a huge role in the results obtained there that one must be very careful when comparing such results and drawing conclusions form those.

Professor

iTrader: (4)

I use the flammable kind.

adamsanders

iTrader: (12)

I go with 93 octane in my 1996. I usually try to get Shell gas if I am near one when I am getting gas; I always heard they had the best gas. I'll also get BP or Speedway, but never the cheapo no-name stations.

Flyer88

Started with 91 when the car was new, and occasionally 93. Then went to 87 due to rising gas prices and noticed a decrease in mileage. Back to 91 and staying there.

preludexl

The cheapest I can find. My 96 Max says premium suggested but regular is fine. No pinging, no knocking.

lightonthehill

preludexl - With today's prices, you have made a wise decision. And your gas mileage will be EXACTLY the same. Flyer88 obviously 'noticed' incorrectly.

Many Maxima drivers think MPG can be obtained from the onboard computer, or by simply dividing mileage by gallons pumped for a tank or two. As was made EXPLICITLY clear several times in this thread, those methods give only a very general approximation, and, for DOZENS of reasons (listed earlier int this thread) are FAR too inaccurate as a tool to differentiate MPG between any two fuels.

There will always be those who think higher octane gives higher MPG, and quote 'real-life results'. But, unless a vehicle is out of tune,


THE HIGHER OCTANE GAS GIVES EXACTLY THE SAME MPG AS 87 OCTANE.