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87 octane in n*


aross2566

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Wow, accidently put 87 octane in my 1999 Eldorado. Then I started to have a problem with it not wanting to start. I first though pressure regulator was going out. But, when I put higher octane back in, problem solved. I didn't know these motors were so sensitive. Still makes no sense to me but, oh well.

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Well, they're not THAT sensitive. Octane shouldn't have that affect on the engine. It was probably unrelated to octane -- water in the gas, "bad" gas, etc.

I've found that both of my Northstar engines ('97 and '01) have run best on premium...but both run just fine on regular. Some people can't tell a difference in driving regular vs. premium, and some can. My cost/mile is the same (better mileage on premium), so I use it.

But the hard starting you experienced wasn't related to the octane.

Jason(2001 STS, White Diamond)

"When you turn your car on...does it return the favor?"

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I seriously doubt that your problem was fuel related. The Northstar has a very effective knock sensor and the pre 2000's will run quite well on 87 (2000+ was designed to run on 87). I ran my '97 on it for 3 years after learning this and never felt any difference.

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Perhaps you got a little water in the gas from that one fill-up.

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-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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I'd even rule out water, and possibly go with "you got a little ethanol in your gas". Water doesn't mix with gas, contrary to popular belief, and will settle out at the station tanks. If you had water in your fuel tank, in sufficient quantities to affect starting, the engine would NEVER start until the water was removed.

Never underestimate the amount of a persons greed.

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Johnny,

I agree on the water part, but I don't understand your ethanol comment.

On another note, ethanol would absorb most of the moister in the tank unless there was an ungodly amount.

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If you have more than 15% ethanol in a car that wasn't designed for it, the PCM isn't calibrated to give you the right air/fuel mixture. Fuels higher in ethanol such as E85 may also harm the fuel system, according to the Owners' manual and the FSM for the 1997 model year.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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Ethanol has a lower vapor pressure than the 13.5 - 15 normal for winter fuel in the north. The south differs a little, as well as the non-attainment areas of the country. The lower rvp can cause hard starting in cold weather, but is USUALLY not a problem. However, I've had some starting problems with a 1999 Silverado, and some with my 5.7 Hemi truck once I began using ethanol (10%) blended fuel.

The gentleman doesn't tell us where he lives, nor the condition of the engine, all of which can be contributing factors.

Throw in a little accumulated water, that may have been hiding in his tank, and as you say the ethanol will blend with it and "make it bigger". Possibly enough to get into the fuel system, but that's pure speculation on my part....just mention it as a possibility.

BTW, as many of you know, I run 87 and 89 octane in my 1999 STS without any issues. I try not to use ethanol blended fuel, but it's becoming harder to avoid (thanks George W.). On my last trip to Pittsburgh, having filled up with 10% ethanol blend, I lost 2 mpg for the trip overall. That's 10% fuel economy drop for me, just by using E10.

I'm not a fan of ethanol.

Never underestimate the amount of a persons greed.

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Same here, not a fan of ethanol. It's a great idea, supports my dad, but it isn't as efficient as it could be right now. I used E85 in my Avalanche for about a month and E10 in my 02 STS for a month also and my fuel economy was hurting. My Avalanche intown mileage went from 14.5 on regular gas to 8 on E85 and my STS dropped about 2 or 3 miles to the gallon with E10 also. You pay a little extra for the regular gas, but it ends up working out better in the end.

-Dusty-

- 02 Seville STS, white diamond

- 93 Sixty Special, Tan with vinyl top

- 79 Coupe DeVille, Tan with Tan top

- 06 GMC Sierra Z71, Black

- 92 Silverado C1500, black and grey

- 83 Chevy K10 Silverado, Black and Grey

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If your gas mileage experience with 10% and E85 is typical, then ethanol is a massive failure. This has been cooking in the wings for some time (no pun intended) as the carbon footprint of Ethanol and the price of food and feed make it less than attractive in the global sense in the short term. If the effective fuel energy is that low and this can't be solved by new designs, then ethanol will eventually be discarded as another once-premising blind alley of automotive technology like the Wankel.

CTS-V_LateralGs_6-2018_tiny.jpg
-- Click Here for CaddyInfo page on "How To" Read Your OBD Codes
-- Click Here for my personal page to download my OBD code list as an Excel file, plus other Cadillac data
-- See my CaddyInfo car blogs: 2011 CTS-V, 1997 ETC
Yes, I was Jims_97_ETC before I changed cars.

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Ethanol is simply alcohol blended into fuel. It doesn't HAVE to be made by corn, but that's the feedstock that skeptics will often use to cast doubt on the technology in general. Indeed, various strides are being made; reference the deal just signed by GM and an ethanol producer to produce ethanol out of solid waste. What a wonderful concept -- trash into fuel.

<a href="http://www.news.com/GM-invests-in-trash-to..._3-6225783.html" target="_blank">http://www.news.com/GM-invests-in-trash-to..._3-6225783.html</a>

Our 2003 Grand Caravan ran wonderfully on E10 and E85. We saw about a 15% drop in economy when using E85...from 26-27 MPG highway to around 21-22 MPG. The price was right also -- we virtually broke even when we could use it. Maybe it's the climate, but our cars see little measurable difference when using blended fuels up to E10.

I don't agree with the politics and tariffs surrounding the reason we use corn as a feedstock. But I absolutely welcome an alternative fuel that doesn't depend on a finite resource, over which we have precious little control. Ethanol is not a magic elixir. It's not a total replacement for gasoline. It's not going to cure cancer. But it needs to be a part of this country's portfolio of energy fuels (especially in the transportation sector). To be clear, this country's competition for petroleum will only continue to explode as Asian countries continue to expand their manufacturing bases.

Edit: one of GM's brands (Saab) has a bi-turbo E85 engine that makes MORE power and gets BETTER fuel economy on E85 as compared with gasoline. Our engines are optimized for gasoline, and not E85. Saying that ethanol is a poor idea because we're trying to use them in engines "retrofitted" for the fuel is like saying Champion spark plugs are bad spark plugs simply because they don't run as good as an AC plug in a Northstar engine. We'll only make real progress when we match the technology to the engine. It's probably no coincidence that this excellent engine is found in a traditionally Swedish brand -- as Sweden has grasped onto E85 fuels with both fists. This country's economy is so entrenched in petroleum, that it'll be hard to climb out. If we don't start now, we'll never get there. Once GM brings these engines that run BETTER on E85, and get better fuel economy on E85, the fuel's stature and respect will change over night.

Jason(2001 STS, White Diamond)

"When you turn your car on...does it return the favor?"

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Jason, I actually think GM created a E100 car also over in Europe.

Back to the topic, I started running my cadillacs on premium starting with my 90 deville, then I got my 95 seville and started running premium for a month and said screw it. It wasn't worth the 20 cents per gallon. It would ping everyonce and a while, but that was about it.

-Dusty-

- 02 Seville STS, white diamond

- 93 Sixty Special, Tan with vinyl top

- 79 Coupe DeVille, Tan with Tan top

- 06 GMC Sierra Z71, Black

- 92 Silverado C1500, black and grey

- 83 Chevy K10 Silverado, Black and Grey

b80385550.jpg

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Dusty, have you tried premium yet in your '02? I've found that my cost/mile is the same. My mileage is up, but so is the cost. Either fuel (87 or 91) costs me close to 15 cents/mile (give or take due to variable fuel prices). You may consider trying it and tracking the mileage for a while. Mine runs better on 91, and I get that performance "for free" (as long as I can keep my foot out of it).

Jason(2001 STS, White Diamond)

"When you turn your car on...does it return the favor?"

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Hey all...

just my .02 here but as I recall from my tech school days, lower octane gasoline has a lower flash point and volatility, so it would be harder to start a cold engine on a very cold day with the lower octane stuff. It would evaporate before it could be utilized for compression and ignition. This could be enhanced by some carbon buildup as it could absorb the fuel before it could be compressed and absorbed. The higher flash point of 93 octane is what prevents knock(detonation) in higher compression engines(pre 2000 northstars) thats why it is recommended. Detonation causes spark advance to be retarded resulting in less power and if severe enough damage and possible meltdowns to pistons and valvetrain.

Bottom line IMHO, use what is recommended by the manufacturer for best results.

In regards to other posts regarding decreased fuel economy, it is a well known fact that ethanol enhanced fuel in on non ethanol engines( non flex fuel engines) has be proven to cause a loss of 2-4 mpg. Now more and more vehicles are coming equipped to handle e85 fuel to circumvent this issue. Trust me, if non ethanol fuel is available, you will see the mpg come bact to pre E85 levels. To the logical mind, this would be preferable, resulting in the use of a lot less fuel due to increased fuel economy. However, the powers that be need to look like they are doing something about the (supposed fuel crisis).

Again IMHO, E85 isn't a long term answer but it is a short term problem, just ask any boater with fiberglass fuel tanks......

Phil

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Edit: one of GM's brands (Saab) has a bi-turbo E85 engine that makes MORE power and gets BETTER fuel economy on E85 as compared with gasoline. Our engines are optimized for gasoline, and not E85. Saying that ethanol is a poor idea because we're trying to use them in engines "retrofitted" for the fuel is like saying Champion spark plugs are bad spark plugs simply because they don't run as good as an AC plug in a Northstar engine.

If it were a simple matter of adding more air (bi-turbo), or increasing compression ratios, it would be easy to retrofit cars to get more fuel economy from ethanol. The fact is that there are less BTU's per gallon of ethanol, and it's BTU content that does the work for us in the end. Otherwise, there wouldn't be any diesel trucks, and diesel cars wouldn't get better fuel economy than comparable models running on gasoline.

You need to be real careful when reading the claims of auto makers and gov't officials when touting the benefits of ethanol. I've read where some unscrupulous (in my opinion) testers only quote fuel economy of the blends considering only the GASOLINE portion of the mixture! This, with E10 would give a 7 or 8% boost to economy using "creative math" alone.

The fact that ethanol production is horrendously energy negative, and each gallon produced requires 1200 gallons of water to manufacture makes ethanol an immediate failure in my book. The only thing keeping it afloat now are the subsidies.

Sorry for straying off topic. (again)

Never underestimate the amount of a persons greed.

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The fact that ethanol production is horrendously energy negative, and each gallon produced requires 1200 gallons of water to manufacture makes ethanol an immediate failure in my book. The only thing keeping it afloat now are the subsidies.

Well, again, you're quoting a statistic of ONE process using ONE feedstock. I don't think that makes ethanol a failure at all. It simply means that the current way we produce it isn't the best means to an end. You can find as many studies out there that quote net energy gains as you can find that quote net energy losses. It tells me that we either don't know what the true balance is, or each study is reporting the results commensurate with the agenda it had when it started the "study".

I agree that we need to find better ways of producing it. The only thing I think we know as fact is petroleum is finite (if you discount the abiotic petroleum theories). Whether we have 10 years left or 1000 years left, doing nothing about it just kicks the can further down the road, and puts the responsibility off to future generations. I'm going to find out first-hand how that works (social security), and I'm fairly certain that I already know the answer... ;)

Jason(2001 STS, White Diamond)

"When you turn your car on...does it return the favor?"

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If it were a simple matter of adding more air (bi-turbo), or increasing compression ratios, it would be easy to retrofit cars to get more fuel economy from ethanol. The fact is that there are less BTU's per gallon of ethanol, and it's BTU content that does the work for us in the end. Otherwise, there wouldn't be any diesel trucks, and diesel cars wouldn't get better fuel economy than comparable models running on gasoline.

By the way, the reason that turbocharged engine makes better use of ethanol than gasoline (as I understand) is because of the octane rating of the fuel. That engine can be tuned for the 100+ octane of E85 with spark timing and the turbocharger via the adjustable wastegate. It's a large reason why adding flex fuel capability to normally-aspirated engines isn't all that effective. You can't add 100 octane fuel to a Northstar engine and go faster. The engine has to be tuned with that fuel in mind. Most domestic engines weren't -- which is why the retrofit notion doesn't always provide great results.

Turbocharging, by the way, is also the only think that makes diesels effective, as you know. The BTU content is only one factor in how much power you can extract from an engine. How the engine makes use of that energy is another factor. Gasoline engines are an incredible waste of energy (TONS of heat loss). It IS possible to get more out of less. As I said before, it's a matter of matching the technology with the application.

Jason(2001 STS, White Diamond)

"When you turn your car on...does it return the favor?"

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Interestingly, this article:

http://www.ext.vt.edu/pubs/bse/442-884/442-884.html

Reports that, "The mainstream conclusion is that ethanol has a positive energy balance, indicating that ethanol contains more energy than it takes to produce", citing 7 or 8 sources concluding such. In particular:

"A Michigan State University study in 2002 found that ethanol produced from corn provided 56 percent more energy than is consumed during production. All those studies take into account the entire life cycle of ethanol production; including the energy used to produce and transport corn, the energy used to produce ethanol, and the energy used to distribute ethanol to the gas station."

It also reports that, "Negative energy balance of ethanol production from corn has also been reported. Two major advocates of this position are David Pimentel of Cornell University and Tad Padzek of University of California, Berkeley. Both professors reported a negative energy balance for producing ethanol from corn. For example, a July 5, 2005, news release from Cornell University states, “Cornell ecologist’s study finds that ethanol and biodiesel from corn and other crops is not worth the energy.”

It appears that the community still can't agree on what is what.

Jason(2001 STS, White Diamond)

"When you turn your car on...does it return the favor?"

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Jason, I totally agree with you. Auto makers need to design an engine to run on E85 that can run on gas, not a gas engine that can run on E85. And make them a little easier for the public to get a hold of. Not a "luxury" item or something to those sorts. I made a program the other day that I can just type in what the price of gas is and what the price of E85 is and it'll figure out how much it costs me to run both of them for 1000 miles. With the price of gas being $3.09 and the price of E85 being $2.34 it ends up being the same. But, that is when I drive my avalanche. If I drive a car that gets better gas mileage then the avalanche, then using E85 is just not economical for me. Then they need some other source of making it to make it less expensive.

It's just like hydrogen right now. It's a little expensive to make because it uses more energy to make it than it puts out, but they aren't thinking wind energy. If they use wind to create the electricity to seperate the hydrogen from the water, you have a completely free energy. Minot has a hydrogen re-fueling station and last year we had 5 or so silverados that were retrofitted to run on pure hydrogen. The cool part was that you could still run E85 and gas in it also. It was just a regular 5.3L. The only bad thing was that the tanks took up the entire box. Our re-fueling station uses wind turbines that are south of town to produce the electricity to produce the hydrogen.

On another side note about diesel, I've heard that GM is going to have a diesel engine as an option in all of their cars within the next few years.

-Dusty-

- 02 Seville STS, white diamond

- 93 Sixty Special, Tan with vinyl top

- 79 Coupe DeVille, Tan with Tan top

- 06 GMC Sierra Z71, Black

- 92 Silverado C1500, black and grey

- 83 Chevy K10 Silverado, Black and Grey

b80385550.jpg

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