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Octane dilemma

In Western SD we are having an issue with 85 octane fuel. The suppliers want to distribute it( our suppliers are from the Rocky Mtns region) but 85 octane does not work well at lower elevations in SD and most cars(including my 2010 Corolla) require 87 octane. It is illegal to sell 85 octane in SD and the suppliers are holding the State and consumers hostage threatening to cut off supplies of 87 octane. Can running 85 octane fuel damage the engine or
void warranties? The alternative is to run premium at 91 and pay more.

Define “does not work well”.

If pinging is present, than the engine is definitely subject to damage. Pinging or (worse) knocking are forms of preignition, and that can definitely do damage.

If the engine is not starting and/or operating properly and smoothly, the assumption could ba made that the combustion process isn’t as good as it should be, and that could result in deposits in and damage to your catalytic converter system.

If the engine seems to run okay but lacks power, it is possible that the knock sensor is retarding the ignition to compensate for a tendency to ping, and if that’s the case it may not do damage…but will reduce mileage.

If pinging is present with 85,
Buy a bottle of octane boost at the parts store or visit a station with a midgrade fuel for sale.
Either way you still ‘pay’ for the higher octane.

I don’t get the part about It is illegal to sell 85 octane, They are going to do it anyway? Most stations I am familiar with have 3 grades of gas, but only 85and 91 are available? The law of supply and demand should kick in and some brand I imagine will continue to supply 87 octane gas. Is this for on base gas stations?

If this isn’t confusing I don’t know what is. On 7/18, KELO reported that it just became legal to sell 85 but stations are supposed to post a warning about using it which they aren’t doing. Then on 7/19 KELO reported that Public Safety said it was illegal to sell 85 but the Governor signed an executive order allowing it, but they bought two octane checking devices. Why? Who knows? But after spending four years there and having many relatives there, I suspect it would be to benefit either the oil companies or the ethanol businesses. Would I use 85? No. Out there I’ve found that the COOPs in particular sell more of the corn stuff so try to switch to another station like Super America, Kwik Trip, or gulp even Holiday who have been designated as a clean fuel supplier.

Um, “supposed” not “suppose”. So much for using the edit feature.

I looked it upa, and it really isn;t confusing at all. It’s exactly as the OP says. It’s illegal to sell 85 octane gasoline in South Dakota. There’s tons of newspaper articles including statements from the SD Attourney General on the subject.

And apparently

  1. stations there have been selling 85 octane as 87 octane
  2. the SD atty gen’l has no intention of enforrcing the law and is instead trying to get the law changed to allow 85 octane.

Gee, I wish I could edit posts…

Criminal charges should be filed if a station is selling 85 octane as 87, SD attorney general should be canned, mis labeling should be a criminal offense. Just to get on my political soap box for a moment if you would please indulge me, I heard Romney say to the NAACP he would eliminate all non essential programs, I have no clue what those are, do you? Edit get firefox, I tried IE and saw your pain. http://www.mozilla.org/en-US/firefox/new/

This points out several things…The number of labs that can and are willing to test gasoline octane are few and far between. Few state agencies have the ability to test for and determine octane…So consumers must have great trust in the labels on the pumps because nobody is checking and the oil companies know it. A large portion of western S.D. is above 4500’ elevation. Most of the western half of the state is above 3000’…This means that 85 octane fuel will do the job without any problems, including cars labeled as needing 87 octane…

The oil companies are making money hand over fist anyway. Selling 85 octane fuel in high altitude areas just lets them make MORE money…The octane may change, but the price does not…

Thanks folks for the responses. My question has been answered. Incidentally the Governor initiated an emergency rule to allow 85 octane temporarily until they sort it out just how the state will allow it to be sold and not be held hostage by the suppliers. Incidentally we do not have the alternate stations(Holiday,Kwik Trip, etc.) metntioned in one response above. Thanks again.

Why an emergency rule to allow octane 85? That governor does not have the peoples best interest at heart, as I see it, It sounds like what is good for the corporation is all that matters.
http://www.argusleader.com/article/20120721/NEWS/307210027/State-warned-western-S-D-could-cut-off-over-85-octane?odyssey=nav|head

Gee surprise, a republican, missed getting rid of walker…

A few years ago Calif passed a law which changed the specs for diesel fuel. All diesel fuel sold in Calif had to change to these new specs. I’m sure it was thought to be for the good. The new formula worked fine in big diesel trucks, but in diesel passenger cars, VW’s, Mercedes, etc, the new formula would often ruin the injection pump and/or other fuel system parts. I forget now if the state had to reimburse or not.

But if the 85 octane damages your engine, you at least can research what happened w/ the now infamous Calif diesel reformulation law as a precedent.