2002 & 2000 Civics - Octane at High Altitude
12-22-2016
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2002 & 2000 Civics - Octane at High Altitude
About 15 months ago, we got a 2002 Civic EX Vtec and a 2000 Civic LX.
I guess there's the general "common wisdom" assumption that these cars run on Regular gas, but being neither of them came with the owners manuals, I'd never checked until a couple of weeks ago. So I checked and it says to use 86 octane in both, otherwise it could damage the engine. So I thought; Uh oh.
We've been using 85 all this time.
So we switched to 87 and I just mentioned it to our mechanic this week, and he said not to worry about the 85, because the only reason they sell 85 here is because we're in Denver. I said; huh?
He explained that higher octane makes the gas burn slower ( didn't know that ) and that because we're in Denver ( minimum altitude is around 5280 feet ) it does that anyway, which is the reason they even have 85 here. ( didn't know that either ) So not to worry about using 85.
True?
I guess there's the general "common wisdom" assumption that these cars run on Regular gas, but being neither of them came with the owners manuals, I'd never checked until a couple of weeks ago. So I checked and it says to use 86 octane in both, otherwise it could damage the engine. So I thought; Uh oh.
We've been using 85 all this time.So we switched to 87 and I just mentioned it to our mechanic this week, and he said not to worry about the 85, because the only reason they sell 85 here is because we're in Denver. I said; huh?
He explained that higher octane makes the gas burn slower ( didn't know that ) and that because we're in Denver ( minimum altitude is around 5280 feet ) it does that anyway, which is the reason they even have 85 here. ( didn't know that either ) So not to worry about using 85.
True?
12-22-2016
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Re: 2002 & 2000 Civics - Octane at High Altitude
2 octane point is not going to hurt anything.
Octane rating is the fuels ability to resist knock. I suppose that could change with altitude, it effects other aspects of the engine.
Octane rating is the fuels ability to resist knock. I suppose that could change with altitude, it effects other aspects of the engine.
Last edited by GolNat; 12-23-2016 at 05:43 AM.
12-22-2016
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Guess my mechanic was right:
http://www.popularmechanics.com/cars...a5308/4345737/
I live in Arizona and use 87-octane regular. In Utah, Idaho and Nevada, stations were selling 85-octane as regular gas. This forced me to pay more for midgrade 87-octane. Is this the latest petroleum-industry scam to get more of our money? Will my car run okay on this bogus 85-octane regular?
A:
Octane is the ability of a fuel to resist knock, and high-compression engines tend to knock more. The obverse of that is that lower-compression engines can run on lower-octane gas. Air is thinner the higher above sea level you go. Less air going into the cylinders means less pressure at top dead center when things go bang. It's a lot like lowering the compression ratio in the engine, reducing the need for high octane. Cars will run just fine on lower-octane fuel when they're well above sea level--and all of those states are. Hopefully, by the time you get back down to denser air, you've burned off most of the low-octane stuff, and can refill the tank with higher-grade fuel.
http://www.popularmechanics.com/cars...a5308/4345737/
I live in Arizona and use 87-octane regular. In Utah, Idaho and Nevada, stations were selling 85-octane as regular gas. This forced me to pay more for midgrade 87-octane. Is this the latest petroleum-industry scam to get more of our money? Will my car run okay on this bogus 85-octane regular?
A:
Octane is the ability of a fuel to resist knock, and high-compression engines tend to knock more. The obverse of that is that lower-compression engines can run on lower-octane gas. Air is thinner the higher above sea level you go. Less air going into the cylinders means less pressure at top dead center when things go bang. It's a lot like lowering the compression ratio in the engine, reducing the need for high octane. Cars will run just fine on lower-octane fuel when they're well above sea level--and all of those states are. Hopefully, by the time you get back down to denser air, you've burned off most of the low-octane stuff, and can refill the tank with higher-grade fuel.
