Recently I have been putting lower octane gas in my car. Is this bad?

 

No it's not bad. You just won't get the full potential of the car.

 

Although you are right to a degree....

I must add this much:

premium gas actually tends to save the engine from catastrophic failure because of its design qualities.

When the engine detects knock it'll pull timing via the ECU and thus the loss of power. But keep in mind there will be some knock prior to that ecu correcting it. Failure only takes a flash to occur. Premium gas is more forgiving on these events where non premium gas is more susceptible to preignite or cause knock rather rapidly ESPECIALLY in high compression engines. Notice in your manual it states that if you do run lower quality fuel to try to mix with higher grade and only run for small periods of time/mileage. This is because prolonged usage will cause damage. Not a matter of if, it's a matter of time before the inevitable occurs.

 

Let's not get into this again

2003-2004 6MT and 5AT SEDANS: 87, with 91 recommended for better performance
2005-2006 6MT SEDANS: 91
2005-2006 5AT SEDANS: 87 with 91 recommended for better performance
2003-2006 Coupe (all): 91

87 will NOT hurt your engine if you fall into the right category.

jdubin94 should use 91.

 

you'll spend the same amount of gas at the pump because of the lower quality of fuel being ran through the motor.

Suck it up, keep using premium and take the lead out of your foot.

 

tell me if im wrong. why would an 03-04 sedan automatic be different than an 03-04 coupe? isnt it the same engine thus being the same octane?

 

Do you have any evidence or reports that back up your statement? Not calling you a liar, but I'm intrigued.

 

THIS MUCH!

 

Actually all 03-04 sedans, AT and MT, are rated at 260hp, while all 03-04 coupes are rated at 280hp; maybe 03-04 coupes timing is more aggressive, hence more hp and higher octane gas required?

 

I doubt that more timing would increase the output by 20hp.. I also don't see how these numbers are correct, I am dead even with coupes if not faster.

 

http://72.3.186.204/refgh0v/og/infin...finiti-G35.pdf
Section 10-3

What you must remember here is TIMING, sedans come programmed differently than the coupe's did. But the internal engine dynamics are the same (compression, bore -x- stroke) So technically the sedan's are just like coupe's again remember everything is controlled with the ECU.

Anyone that does not believe anything I am stating... PROVE ME WRONG. Go to a dyno use 87 octane, and show me how the gas is not any better than 91 or higher. I can assure you that after that experience you'll see otherwise.

Bottom line, can you use inferior gas: Yes.
Will it slowly hurt the engine: Yes.
Will you have a loss of power: Yes
Will you consume more gas: Yes*

















* you will consume more gas because of the nature of the ecu's job. When the ecu detects knock it retards timing, and adds more fuel to quench the pistons (for more cooling). Since the ecu is detecting pinging/knock it'll add loads of fuel to compensate for the occurrence thus consuming more gas.

 

In the long run yes its bad for the engine.

 

Guy, don't worry about the gas. As long as you don't get some bad gas from a bad station you car and engine will be okay.

I have been running the cheapest gas I could find since my car had about 40,000 miles, I am just about to hit 198,100 and the engine still run like it was brand new. No issue with the engine.. (this is a 2003 sedan, BTW).

 

Ahem...







https://g35driver.com/forums/g35-sed...-designed.html

Search next time...

 

LMAO

Using 87 will cause your engine to blow up, rich.

Tuning is different, hence the different rated HP. Despite many peoples speculationa bout the HP ratings, the tuning maps ARE different, also, the differnt HP ratings DIRECTLY follow the recommended Octane by Nissan. Not a coincedance IMO.

You can doubt it but it's super simple to gain 20hp with tuning. Also, consider that this is BHP, NOT WHP, so as such, it's even easier to gain 20 BHP with tuning. If they wanted to push it further it'd be easy to get 20 WHP out with different tuning.

The Coupe also has a different exhaust, etc. 20 BHP is no where near out of the realm of possibility.

Your sedan is lighter, and 20 BHP is not a lot, age of the engine would even that score even if weight was the same, not to even get into the millions of other variables in your open-ended comment.

Thanks, saved me posting it

Dunno whether OP has 6mt or 5at though. But follow the above, and you're good.


Oh, wait, before this thread dies off, can't forget, enter the guys who will comment "I have run the cheapest crap for xxxxxx miles and everything is perfect, so don't listen to Nissan or their recommendations or antyhing, I regularly race Coupes and 350z's and beat them on cheap gas no problem."

I love evidence packed statements like this^^