Bogeygolf

This is my first car "requiring" super unleaded. I've read many places claiming that cars these days just don't need super unleaded and you can get away with regular no problem.

Anyone use regular and if so, any problems? Could there be long term damage by using too low of an octane?

Thanks

jesseenglish

The 350z is a high compression motor. If you put low octane fuel in it you will get pre-ignition. Pay the extra cost of the higher octane fuel, your engine will thank you for it.

MyZ4U2C

Last week i was at the gas station and notic ed that they had inadvertantly set the price for both 87 and 89 octane the same on two pumps. I was about to go on a road trip so filled up with the 89. I had no problems whatsoever...no detonation and MPG's were fine. I would not make this a habit by any means! Also, i dont know what would have happened with around town or agressive driving. In the owners manual it states that you can use mid-grade gas but at reduced performance.

lowrider

iTrader: (3)

If you use a lower octane fuel, the electronics (ECU) will compensate for it, and performance will be reduced. I also put in some 89 octane by mistake, but luckily my wife was with me and noticed what I did. She stopped me in mid fill, and I finnished up with 91. So with my mix, I ended up with around 90. I noticed no ill effects, but I wont make that mistake again.

Lou

oscarmayer00

Don't worry 87 octane will be fine, if you race you should use 91 octane to get the most out of the engine.

If you use a lower octane fuel, the electronics (ECU) will compensate for it, and performance will be reduced at the high end.

How can you tell if you’re using the right octane level?
Listen to your car’s engine. If it doesn’t knock you’re using the right grade of gasoline.

Unless your engine is knocking, buying higher-octane gasoline is a waste of money. Studies indicate that altogether, drivers may be spending hundreds of millions of dollars each year for higher octane gas than they need.

What are octane ratings?
Octane ratings measure a gasoline’s ability to resist engine knock, a rattling or pinging sound that results from premature ignition of the compressed fuel-air mixture in one or more cylinders. Most gas stations offer three octane grades: regular (usually 87 octane), mid-grade (usually 89 octane) and premium (usually 92 or 93). The ratings must be posted on bright yellow stickers on each gasoline pump.

Should you ever switch to a higher octane gasoline?
A few car engines may knock or ping — even if you use the recommended octane. If this happens, try switching to the next highest-octane grade. In many cases, switching to the mid-grade or premium-grade gasoline will eliminate the knock. If the knocking or pinging continues after one or two fill-ups, you may need a tune-up or some other repair. After that work is done, go back to the lowest octane grade at which your engine runs without knocking.

Is knocking harmful?
Occasional light knocking or pinging won’t harm your engine, and doesn’t indicate a need for higher octane. But don’t ignore severe knocking. A heavy or persistent knock can lead to engine damage.

For More Information:

The FTC publishes free brochures on many consumer issues. For a complete list of publications, write for Best Sellers, Consumer Response Center, Federal Trade Commission, 600 Pennsylvania Ave, NW, Washington, DC 20580; or call toll-free 1-877-FTC-HELP (382-4357), TDD 202-326-2502.

MyZ4U2C

I would NEVER use 87 octane in this car.

Tweety-nator

The owner's manual specifically states to use lower octane gas (87 octane) ONLY if 91+ octane is not available, and ONLY TEMPORARILY until 91 octane gas can be obtained.

This was taken from the manual:

FUEL RECOMMENDATION
Use unleaded premium gasoline with an octane
rating of at least 91 AKI (Anti-Knock Index)
number (Research octane number 96).
If premium gasoline is not available, unleaded
regular gasoline with an octane rating of 87 AKI
number (Research octane number 91) may be
temporarily used, but only under the following
precautions:

- Have the fuel tank filled only partially with
unleaded regular gasoline, and fill up with
unleaded premium gasoline as soon as possible.

- Avoid full throttle driving and abrupt acceleration.

Whataguy5431

It seems that's all we have around here. What will "too much" octatne do over the long haul?

afr0puff

iTrader: (1)

You guys "paid" for performance with this car. Why would you cheap out on skunky gas?

Sunoco Ultra 94 baby!

Too much octane can be bad if you add octane boosters. I think it causes the fuel mixture to become too rich and can burn out some sensors. But this is only if you go above 100. Can you even go higher than 94 without additives or special fuel?

jckolnturn

iTrader: (1)

Using lower than recommended octane is bad news and waiting until you hear knocking is ever worse advice. If you can hear knocking with just your ear while driving your car it's too late because that means it's either knocking at idle or the knock is so loud that you can hear it at WOT both of which mean the end of your motor. The ECU will operate the motor at a very rich level if you put in lower octane gas but this is more to idiot proof the car if you can't get the right gas one time rather than to save you a few pennies a gallon on a regular basis. What are you really saving anyway, you're just going to need to tune the car up more often and you burn more gas due to the rich condition. Using too much octane is no problem at all for the car it just costs more. Here in NY I use 93 octane, and i was curious to know if anyone knows what happened to the 94 octane Sunoco used to sell?

dchengmd

Most cars made today requiring/recommending 91 octane will compensate for a fill of less than 89 or 87, but like the others here have said, don't make a habit of it.

The term 'Premium' gas has probably done more to dupe the general public into paying more $ for gas than anything else. "Hm, this gas is premium, so it's better than 'regular' gas, so I'm going to use it in my stock Civic to make it run better and faster!"

topdown-z

Lets see.....................

You spend $30,000 --- $40,000 for a Nissan Z and then decide you want to see if it will run on something less than premium fuel.

Yea, I guess it's a pretty good deal to save about .10 a gallon.......NOT

Maybe you can supplement the fuel with a little water...just don't take it off of idle very often. Heck, if most of your driving if downhill, why not just quit buying gas all together. That way you can just buy gas when you need it for special occasions.

Just Remember:

YOU CAN DRIVE A CAR WITH YOUR FEET...BUT THAT DOES NOT MAKE IT A GOOD THING!!!

03Brickyard

There is only 87, 89, and 93 around my way... I always use 93.... is that bad???

Tweety-nator

93 is fine.

mofoz

iTrader: (1)

93 is fine. Thats all we have here around chicago. Besides the 89 and 87 octanes.

FairladyZ

93 baby

lowrider

iTrader: (3)

Yeah - 93 is fine. Wish I could chose 93! Out here in the west, Premium is only 91. It was 92 up until a couple of years ago, when we got California's crappy gas.

Lou

Montez

I agree if your going on a long road trip with out lots of stop and go 89 oct. is fine, for stop and go city driving stick to premium 91-93 oct. depending on where you live.

themyst

iTrader: (1)

they still sell 94 at sunocos.

mofoz

iTrader: (1)

theres no point in being cheap on gas, only thing it can cause is problems, and even though you may not play on slamming on the gas to pass someone, we all know how it just seems to happen.