joecraps

Sorry if you have seen this before. It shows how something as simple as not running the correct octane in a Maxima can make you crazy.

http://www.samscars.com/gf50.html

Frank Fontaine

It's so much simpler than this guy makes it out to be. He acts as if he's up for a Nobel prize or something.

Owner's manual wants 91. Grades come in 87, 89, 93, 94. Short of custom blending, the only way to satisfy the owner's manual is to use super. Super is 17 cents more than regular, which is now 2.599. Fuel is artificially priced, i.e. super is 6.5% more than regular, unlike when regular was .899, super was 22.25% more than regular. Conclusion is if you can afford the price of super from a relative standpoint, buy it, it is dirt-cheap today. However, if 2.599 is already stretching your pocketbook, then super is expensive in an absolute way.

Mercedes Benz has stated time and time again that premium is recommended, however, because their vehicles are used in virtually every country in the world, many of which do not have 87 octane, the vehicles can be run on sub 87 but with lessened performance.

I can't understand why everyone wants to explain it in such difficult and complicated terms. Buy your fuel based on price, that is what you and your pocketbook feel comfortable with. We've been through predetonation about 1,000,001 times on this forum.

RHMax

The manual actually states 91 octane rating OR HIGHER, not excatly 91 oct. Higher octane usually yield high MPG, but do what ever suit your wallet. Just don't cry IF/WHEN your engine knocks and pings.

MB does recommend higher octane fuel because of better engine performance. MB also offer more engine choices through out the rest of the world than in the US, US models gets better engine options. In parts of the world where gasoline prices are higher or lower in quality, MB offer same cars with different engines, same w/ Nissan and other car makers. Bad example.

Frank Fontaine

Absolutely, positively, WRONG. Higher octane prevents predetonation. Nothing else. PERIOD. You do not unleash more energy from higher octane fuel. That's why when you use premium in a vehicle designed for 87, you simply burn up the fuel without any benefit whatsoever. Higher mpg. Please, do your homework.

RHMax

Got me, Frank. What else was I WRONG about?

HOMEWORK:
http://www.lubedev.com/articles/octane.htm
http://www.ftc.gov/bcp/conline/pubs/autos/octane.htm

Do I get an "A" now?

njmaxseltd

iTrader: (19)

Those two articles tell it like it is. There is absolutely no reason to use anything higher then whats recomended for your car. Your only wasting money on fuel, plus you can actually decrease performance if your octane rating is to high for your engine.

Bobo

I found the above article, "Octane and Mileage", to be extremely interesting as I have been queried in the past about my mileage claims. This happened as recently as yesteray.

I have exceeded 500 miles to a tank of gas at least 15 times and 550 miles about 3 times, albeit with the tank down to fumes.

I live at the coast of British Columbia. The author of the above-mentioned article states: "I found Canadian gasoline is vastly superior to gas sold in the U.S. ....One reason is that Canadian gas has no alcohol."

I have run 89 octane gas about 80% of the time with no ill effects and have owned the car since day 1. However, I bought a tank of Chevron 89 last March in Blaine, Washington and the car ran like crap. I ran Chevron 92 octane most of last winter and really didn't notice any difference, albeit it was winter gas. I am presently running Husky 90 octane, a new gas being sold at 87 octane prices. It has 10% ethanol and the Max seems to run just fine with it.

I have never bought 87 octane and have no intentions of doing so.

If you are ever in Canada, cough up a lung, and buy a tank of Canadian gasoline.

nismos14

iTrader: (56)

I've seen stations ranging from 87,89,90,91,92,93,94,95,100 octanes.

RHMax

That's what the environmentalits would say about Canadian gasoline. Ethenal burns clean, but from the article, it also reduce the MPG, which means burn more gasoline per mile How does that make sense???

Frank Fontaine

Wow, with 100 octane our Maximas could probably get better mpgs than a hybrid! That would be 27k in savings!

Octane is what it is. The motor will run best with what it was designed for. But when you exceed the recommended octane, there is ZERO benefit. AKI is just that. The new CR-V requires 87, put all the 93 in it you want, the mpg will not go up, the motor wont last longer, you wont get it more times a week as a result, the Red Sox wont win the Series this year again, you get the idea....

Frank Fontaine

Hey, it's not so bad as our US dollar has collapsed. There were French people all the time at the Jersey Shore when the exchange was over 1.6, so now that it's below 1.2 Canadians have it good. Plus due to NAFTA if you have a professional job you get a TN visa just for the asking.

I'll be in BC this December. Finally doing the Whistler thing. Dirt-cheap airfare, not really sure how they do it (NWA).

maxspeed96CT

iTrader: (9)

well ive ben running only 93 and i got cell and lots of other problems???

seeker51

so, better mileage with premium, even with a knock sensor which adjusts if you use 87?

nismos14

iTrader: (56)

It doesnt ADJUST, it retards timing, which causes worse performance.