Actually, no he didn't. You initially confused the issue by erroneously invoking the name of Satan Ethanol in connection with Costco premium fuel (91AKI octane), then corrected yourself after checking some facts.

Had you been right about the fuel actually being E10, it still would not explain the difference in fuel consumption. Given that E10 contains 97% of the energy of pure gas, Dennis' mileage would have increased by about .7 mpg, not the 2.5 mpg difference reported.


Of course. the OP always has the option of asking more question when he thinks there's lack of consensus or when it's obvious he's being baffled with BS..

I did see the last line of post #35 and got a good chuckle from it. There was no need to reply anyway as the subsequent post by Jag V8 said what I would have anyway. I've already pointed out several times that all fuel in a geographic area comes from the same refinery or two refineries in large areas, so switching brands would change nothing in that respect.

One unanswered point- no, the car's computer does not compensate when switching from one brand to another. Even if there was a tangible difference from one brand to another, it has no way of knowing what it's being fed.

The lack of response to this question sorts of indicates that nobody knows, but more probably that nobody cares.

 

I'm not a moderator, and don't even play one on TV, but it's probably time to let this thread fade off into the sunset. Seems like a bad case of LWS.

Sorry, Dennis

 

Who knew this thread would go as far as it did. I think my original question was pretty much answered within a few responses when I learned that Costco was a Top Tier gasoline and a couple MPG difference is no indicator of a significant difference between brands. I pretty much tuned out at that point but I have the feature where I get an email showing new responses to the post so a glanced at them as the discussion continued. As is the case many times, information comes out well beyond the original question or topic and this is actually one of the benefits of this group. My guess is that more than a few people got the benefit and learned something from the extended discussion both about the original question and the additional topics covered or argued. Again, that is the value of this group and hope it continues.

 

>interesting that Costco premium is ethanol free in Canada.

That's just because the Arthur Daniels Midland (ADM) corn lobby isn't quite as powerful north of the border...
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Current Hers: '13 Lexus ES350
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No, we have plenty of E10 in Canada and have had it long enough (since the mid-70's) to know that all the sky is falling stuff is over-exagerated.

We have our own laws and political agendas. Almost like we're a different country or something.

 

Canada mandates an average minimum ethanol content in gasoline of 5%. Some suppliers meet this spec by putting (up to) 10% ethanol in other grades in order to keep Premium ethanol-free.

 

>Canada mandates an average minimum ethanol content in gasoline of 5%

Ah, so the corn-lobby is active up there, too... ;-)

That's interesting, though, I didn't think much corn was grown in Canada.
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My karma just ran over your dogma
Current Hers: '13 Lexus ES350
Current Mine: '08 Jaguar S-Type 4.2 "Satin Edition" (250.06 whp / 259.67 torque)