NEW G35 owner....Do I HAVE to use Premium ?

[Hookm36]

It sais use premium, just curious what gas you guys use, and if it will hurt the car using the middle grade. If it wont hurt the car, id rather not hurt my pocket.....

[Sr20 Riot]

I heard you use Diesel?Hmm?

[zozoka1212]

welcome to nico

I use premium. It is recomended by infiniti. If you want to keep your car for several years than it worth. If it is a lease than might not worth.

Zozoka

[SVTCOBRA]

Either use prem. or trade it in on a camery....... OK, never got to use those icons before.....so yes, I'm So, if it's a long term deal - prem.If it's a lease - whatever.However, I would use prem. regardless.

[suby01]

why would you ask?? p.s. you need to put in drive for it to move forward.

[redhed]

high octane will net you the best performance...but i seriously doubt you'd hurt the engine using mid octane...unless you notice alot of pinging when you get on the throttle...

[G_whizz]

Down boys...easy with the flaming!

If you own the car...definitley use premium, if not and it's a lease...take a gamble if you want!

[BigWill]

Amen, Rich!! lol

I seriously doubt that the engineers would go to the trouble and expense of designing a high performance engine, built to run on high octane gas, then spell out in the owners manual that they recommend at least 91 octane, just for S**** & Giggles. If you're running a low compression engine that is not tuned for performance, use kerosene if you want... but these cars run better, and cause less stress on the engine when burning 91+. I personally don't care for the attitude that 'if it's a lease, who cares?', but that is just me, and is not a judgement. I don't care whose car I am driving, I take care of it as if it were mine.

Ok... done with the soap box. You want it back Rich?

[champagneG35]

Just my 2 cents and whether or not it's viable is anyones guess due to the fact I heard it from the dealership I now hate . Anyway I was told by the salesman that they used only 87 in all their Gs due to the fact the cars computer compensates timing and what not so it doesn't have issues and that according to their techs in performance wise you wont get all of your horsepower by using the lower grade (I believe the number was 5-10hp loss). I know I took his word for it for like the first fillup when gas prices were even higher than they are now. After that I've used 91 and never looked back but I did not notice any pinging even at full throttle, which btw will sound like you're running over lots of little rocks that are hitting the underside of your car.

FWIW~~~Mike

[BigWill]

So, let me see if I understand you correctly.

The Owners Manual recommends 91+, but the dealer, who, by the way, gets paid to repair your car when it breaks, says 'go ahead... use regular, we do it all the time!'

That almost seems like a shark telling you, 'come on in... the water's fine!'

Why cause the computer to have to work harder to correct something that wouldn't happen if you were using the right octane grade.

[rg_g35x]

Guys, a quote from page 379 of the owner's manual: FUEL RECOMMENDATION INFINITI recommends the use of unleaded premium gasoline with an octane rating of at least 93 AKI (Anti-Knock Index) number (Research octane number 98). If unleaded premium gasoline is not available, you may use unleaded regular gasoline with an octane rating of at least 87 AKI number (Research octane number 91), but you may notice a decrease in performance.

My understanding is the the engine management computer will use the knock sensor to detect detonation (also known as knock or ping) and it will retard the ignition timing slightly to accomodate. The engine management computer does this all the time anyway, regardless of what grade fuel you put it, it's just with 87 (rather than 91 or higher) it will just retard the ignition more, which results in a reduction of horsepower.

In the 'old days' (pre-knock sensors) you could damage the engine, but with the modern engine management computer/software, I don't think it's a problem since the computer and the knock sensor are constantly monitoring the situation and adjusting as needed. Since the manual states that you CAN put 87 in, I would say that if damage occured as a result of putting 87 in, then Infiniti would have to cover it under warranty.

[Q45tech]

If you lease or sell before junk yard hopefully the next owner won't find you and extract punishment for destroying his dream.

What you do to your own car is your business unless you try to resell it, then it becomes their business.

The warranty excludes fuel damage because they cannot control what you buy. Anyway engine damages rarely show up under warranty. They build them at least that good.

[rg_g35x]

Q45tech, I don't get what you're saying. Are you saying that running 87 is going to damage the engine? I run 91 (not many gas stations around here carry 92/93) because I want to get the most horsepower out of my car, but I don't think running 87 isn't going to damage it, since the engine computer will just set the timing back a little to avoid detonation.

[redhed]

what i find the most interesting is that my '06 owner's manual says the automatic g35 sedan can use 87 but the coupe should use 91. the automatic coupe and sedan both have the same power and torque ratings!! i think it's pretty safe to say you can use 87 octane in the automatic coupe. the manual coupe may have a slightly different ignition and fuel system vs the automatic since it has a different power/torque rating...

i run 91 or higher in my car simply because i like the extra kick in the butt i get when i'm flogging it...the car that is!

[redhed]

So, let me see if I understand you correctly.Why cause the computer to have to work harder to correct something that wouldn't happen if you were using the right octane grade.

a computer has no concept of what work is...so who cares!

[Q45tech]

I buy 93-91 octane [without ethanol] to get the higher level of detergents to help kept the internals clean...[premiums usually have more detergents]...............the octane is a bonus especially in Summer.

You cannot lump all refiners together and each hours production will be different, hoever much gets dumped into a family holding tank at the tank farm so the good gets worse and the bad gets better.........sometimes.

[BigWill]

I think you might have missed my point. I just mean that why would you want to make your cars management system work extra hard to make corrections that it otherwise wouldn't need to if you used the recommended fuel? I know that the computer doesn't know the difference, but when you go for an oil change, do you ask for the cheapest oil possible? Do you disregard the recommended anti-freeze and go with whatever costs the least? I just have to laugh when someone will spend 30 or 40k on a performance car, and then begin to try to 'cheap it down', and complain about the gas mileage, or want to use an inferior fuel, or ask why the tires and brakes don't last. I understand that everyone wants to get the most from their money, and I am no different... but when you are talking about a difference of maybe 25 or 30 cents per gallon, which, for a full tank of gas comes out to only around 5 or 6 dollars, if that kind of money is that big an issue, why not just buy a hybrid for half the price, and get 40 to 45 mpg and stop worrying about it?

Believe me, I understand that this entire thread is an example of an issue that is about personal choices and beliefs that will not be decided here... and I don't begrudge anyone for doing what they feel is right based on those factors. It is my personal belief that one should at least try to follow the recommendations of the car manufacturer, and I understand that I won't have that extra $5 in my pocket. That's ok with me.

To answer the author's original question, no, you don't HAVE to use the recommended gasoline, no you don't HAVE to do anything that is outlined in the manual. Will it cause damage to your engine? The experienced techs here seem to feel that it will, long term. Do you believe it, or even care? That is the more important question to ask yourself.

[redhed]

I buy 93-91 octane [without ethanol] to get the higher level of detergents to help kept the internals clean...[premiums usually have more detergents]...............the octane is a bonus especially in Summer.

You cannot lump all refiners together and each hours production will be different, hoever much gets dumped into a family holding tank at the tank farm so the good gets worse and the bad gets better.........sometimes.

problem is you really never know for sure what you are getting when you fuel up...even with so-called premium. i'll give you an example...i recently filled up my g with high octane at a local gas station. the next day i noticed it wasn't running quite right for the first 30 seconds after a cold start. and it seemed really down on power. low and behold the local transporter had put diesel in the wrong underground take at the gas station! luckily it didn't harm my car...just caused a service engine soon light.

anyway, i loathe the word premium when associated with gasoline...'cause in many instances there really is nothing premium about it. imo, gas has been tagged premium to make people feel like they are treating themselves, and their vehicle better by burning this more expensive stuff, even when their vehicle gets absolutely no benefit from it.
Modified by redhed at 2:52 PM 4/22/2007

[redhed]

To answer the author's original question, no, you don't HAVE to use the recommended gasoline, no you don't HAVE to do anything that is outlined in the manual. Will it cause damage to your engine? The experienced techs here seem to feel that it will, long term. Do you believe it, or even care? That is the more important question to ask yourself.

until someone can actually show me a 3.5l g35 motor that suffered from premature failure due to using 87 octane...i'll still say that an automatic g35 coupe or sedan can certainly live a long, happy life on 87. but to each his own...

[champagneG35]

problem is you really never know for sure what you are getting when you fuel up...even with so-called premium. i'll give you an example...i recently fill up my g with high octane at a local gas station. the next day i noticed it wasn't running quite right for the first 30 seconds after a cold start. and it seemed really down on power. low and behold the local transporter had put diesel in the wrong underground take at the gas station! luckily it didn't harm my car...just caused a service engine soon light.

anyway, i loathe the word premium when associated with gasoline...'cause in many instances there really is nothing premium about it. imo, gas has been tagged premium to make people feel like they are treating themselves, and their vehicle better by burning this more expensive stuff, even when their vehicle gets absolutely no benefit from it.

Ok I hope I don't start a huge debate about this but I just wanted to state one thing about the underlined portion above. Our cars or at least the 03 coupe I know has a 10.5 to 1 compression ratio. Now granted we have this smart computer that retards our timing should we have to put less than 91+ octane in it. On the same token however have you ever driven something with that high of compression without the computer on 87 octane ? I have. My two motorcycles a 1990 FZR1000 and it's little brother the FZR600 which have the same compression ratio and no computer will run absolutely like crap on 87 octane sputtering and popping and overall barely running coupled with dramatic power loss. So what happens if we're running 87 octane in our cars and the computer has a problem effectively eliminating the timing control. Now I'm not 100% positive but I would assume there is a preset default it will fall to should it have a problem like that and if I were to guess I would say that it would default to factory specs with recommended timing. That would mean at this stage there could be possible damage to the engine from knocking/or pinging. Just my 2 cents.

[BigWill]

but to each his own...

I couldn't agree more bro. That was what I was saying, in far too many words.

[redhed]

Ok I hope I don't start a huge debate about this but I just wanted to state one thing about the underlined portion above. Our cars or at least the 03 coupe I know has a 10.5 to 1 compression ratio. Now granted we have this smart computer that retards our timing should we have to put less than 91+ octane in it. On the same token however have you ever driven something with that high of compression without the computer on 87 octane ? I have. My two motorcycles a 1990 FZR1000 and it's little brother the FZR600 which have the same compression ratio and no computer will run absolutely like crap on 87 octane sputtering and popping and overall barely running coupled with dramatic power loss. So what happens if we're running 87 octane in our cars and the computer has a problem effectively eliminating the timing control. Now I'm not 100% positive but I would assume there is a preset default it will fall to should it have a problem like that and if I were to guess I would say that it would default to factory specs with recommended timing. That would mean at this stage there could be possible damage to the engine from knocking/or pinging. Just my 2 cents.

i suspect that if the electronics/hardware of a g35 loses it's ability to accurately advance or retard timing...it either won't run at all; or it will flash a "service engine soon" light.

[Hookm36]

so uughhhh................I think my question got answered.....

Thanks BigWill. !!

will continue to use Premium....

[BigWill]

so uughhhh................I think my question got answered.....

Thanks BigWill. !!

will continue to use Premium....

LOL... You're welcome Paul. Sorry for the long rants and raves. Unfortunately you "hooked" into a long-contested point here on the forum. That particular topic always sparks heated debate! (but I guess that was pretty obvious)

[Hookm36]

OFF topic........but how do i post pictures on the site ?.....would love to show my new rims later this week !!

[BigWill]

Paul...I tossed you some instructions as a reply to your post in the Members Rides thread. Can't wait to see your ride with the new shoes!