I have a 2007 G35 and have been gassing up at a local Kwik Trip (Wisconsin & Minnesota brand). Their 88 octane states it contains up to 15% ethanol and is designed for flex-fuel vehicles. The 91 octane (which I have been using) states No ethanol added recreational gas – For use in collectors vehicles or vehicles eligible to be licensed as collectors vehicles, off-road vehicles, motor cycles, boats or small engines only.

Have I been using the wrong gas?

 

I think the 91 octane no ethanol would give you marginally better gas mileage/performance, while the 15% ethanol will give you marginally better emissions. I would use 91 no ethanol if it was available where I live.

 

So using this gas should not pose any problems/issues?

 

It should pose no problems, I would use it over the E15.

 

87-88 octane gasoline with up to 15% ethanol is completely normal in the midwest US and could be elsewhere as well. Probably 75% or higher of drivers use that in their cars. In cars, you don't hear about issues related to ethanol. It can be a pain in small engines - lawnmowers, weed trimmers, etc if you don't keep it fresh.

In the VQ36HR, Nissan recommends 91 octane but do not require it. It is perfectly fine for your G35 too. That 'note' is very odd. Is that on the pump ? What station is this ? Around here, there are very, very few places that you can get ethanol-free fuel. I think even the mid-grade and premium grades include ethanol. If you want ethanol-free, stations near lakes usually have it for boats but it costs a LOT more, like $1 or more per gallon.

How much is regular gasoline and how much is this 91 octane ?

 

On my third Infiniti
06 G35 6 speed purchased new, traded in at 171796 miles
2012 G37S 6 speed purchased new traded in 94444 miles
Present 2016 Q70 6600 miles
Never used premium on any of my vehicles
Regular 87 octane all the time



Telcoman

 

The higher the octane, the less likely it will prematurely detonate. Therefore 91/93 is safer to use. *** long as all of your sensors are working properly and the ECU is receiving the correct signals, 87 will not harm your engine.

 

 

Summers in NJ are hot
Winters in NJ are cold
With the 06 I was commuting 2k miles/month
Some working at home with the 2012
A few trips per year from NJ to Florida on all vehicles
Rarely over 80 MPH
Rarely over 5k RPM

Telcoman

 

The engine will pull timing advance before the engine is ever damaged as long as your knock sensor is actually bolted to the engine like it should be. However on hot days running the engine hard you will lose that timing advance that you would otherwise be able to take advantage of if you are using lower octane fuel.

Never use anything less than premium fuel if you are doing a track day.