Basically what they all said, I was doing a bunch of research on gas, cause i was bored, but basically octane is an ignition retardant, our engines are high compression engines which means if you run a low octane you risk the fuel igniting and cause pinging etc, so if you are in a really cold climate like me (I'm FREEZING OVER HERE) it's okay to run 87, not recommended but the cold air etc should mean it'll keep the pinging to a minimum, I don't run anything lower than 93, you blow 30 k on a car I'm not going to risk killing the engine to save like 50 bucks a year.

On the point about the SES most likely the gas Cap, even if it was loose and you went back and tightened it again it'll take something like 40 key cycles for it to clear, so i'm pretty sure it's that, happened to me too after my first fill up guess we are not used to that type of gas cap. hope this helps.

 

The SES light...

May not be the gas cap .. I had 200 miles after my first fill up and my SES light came on .. it was read as "LOW VOLTAGE GROUND FAULT" ..

Turns out that these G's that sit out on the lot .. the batteries get drained and the first few hundred miles the battery isn't completely charged... particularly if it's cold out .. my dealer, I mean stealer, cleared the code, and it's never come back...

Everyone jumps on this gas cap thing, but it's not always that.

 

Us folks in Cali dont have the privilege of 93 octane

 

Your premise is correct, but you forget that in modern automobiles, the spark is tightly controlled by the engine computer - any knocks and pings are taken care of automatically. You may see less efficiency with lower octane, which can lead to lower output and/ or lower MPG. In other words, you aren't hurting the engine, but you aren't saving any money, either, since you are getting fewer miles per gallon. By the same token, putting in higher Octane won't get you more power. For best results, stick to the manufacturer's recommendations.

 

Yeah... which is basically what I said way up at the top!

 

ahhh, okay what he said too, My research was for my old car where it jsut ran on regular, and so I found out that is an engine ran on regular and is designed for regular running a higher octane gas was pretty much a waste of money. Thanks for clearing that up.

 

strange observation...

when i bought my car i asked the salesman which gas is recommended to use. he said typically 91(93 not available in my area) but he said because were at a much higher elevation i can use 87 and be just fine.. just for grins i tried both and i get better MPG with the 87 also the car seems to run a little better..seems more sluggish with 91

also what are you guys getting for avg mpg. i drive 60/40 highway to city and barely manage over 18.

 

i use 93 here.....

I do not know much about the engine, but all i know is that when i open the gas-flap, there is a sticker that says "premium only". This got me wondering, if nissan said the engine works with regular, why are they making us fill up with premium.

I would not mind saving a few extra bucks a month, but i hope i am not using premium just because it is branded as "Infiniti". Which reminds me, the new Maxima i believe requires premium as well.

 

Different versions of the VQ engine have different requirements depending mostly on the compression in the cylinder. Some of you folks may require 91; for others it is recommended. These blends are not that well controlled so you might want to bump up an octane level to be on the safe side. Early detonation is very hard on the engine. Good thing the ECU can sense it and adjust the spark timing to some extent in order to compensate (assuming your anti-knock sensor is working properly). Still, does that sound like a smart way to run your machine? Probably not.