# Does ethanol-free premium perform better?



## Mack (Nov 8, 2016)

I think it runs better and cleaner. That might all be in my head, though, as I haven't seen any mpg or hp difference on the torque app while running it. I'm not a fan of ethanol, so I guess I'm just happier running efree when I can get it.


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## 6speedTi (May 18, 2018)

At first when ethanol was introduced vehicles took a small hit in fuel economy. As time went on the vehicle manufactures remapped the ECU to run better on 10% ethanol. Then 15% was introduced in some states and as time went on they remapped the ECU somewhere around 12% to 13% ethanol. So todays newer vehicles are better setup for ethanol. If you run straight gas with newer cars I don't know how your mileage or performance will change if at all.


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## Barry Allen (Apr 18, 2018)

My prior car was a 2009 Hyundai Accent. 

There used to be a very small Shell station in my city where the owner (who worked there for like 64 years before retiring) sold ethanol-free gasoline. You could get regular or 91 octane premium for about 10¢ per gallon over the price of anyone else it town. I never noticed any difference in fuel economy between his fuel and 10% ethanol fuels. I continued shopping with him to support a small business.

There was also a fuel station with an ethanol blend pump where you could choose 10%, 15%, 30%, 50%, or 85% ethanol. 50% would throw a CEL but 30% would not. Routinely filling up with 30% would decrease my fuel economy by about 3-5% but the price discount was far greater than that, so it was economically beneficial to fill up with 30% ethanol fuel.

At my parents' house there was a Phillips 66 station that offered 93 octane premium, but it was 10% ethanol. Another notable oil company with a fleet fueling station sold ethanol-free 87 octane at an outrageous markup. That oil company closed their fleet fueling station so the Phillips 66 stations in town (3 of them) now offer ethanol-free premium, but the octane rating dropped from 93 to 91.


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## Barry Allen (Apr 18, 2018)

6speedTi said:


> At first when ethanol was introduced vehicles took a small hit in fuel economy. As time went on the vehicle manufactures remapped the ECU to run better on 10% ethanol. Then 15% was introduced in some states and as time went on they remapped the ECU somewhere around 12% to 13% ethanol. So todays newer vehicles are better setup for ethanol. If you run straight gas with newer cars I don't know how your mileage or performance will change if at all.



For carbureted engines it did offer better emissions. The extra oxygen in the fuel with the 10% ethanol basically tricked the engine into running a lean mixture so you got somewhat better tailpipe emissions. 

The biggest problem/fraud with 10-15% ethanol is we use it as an octane improver. Oil refineries blend regular unleaded to something below 87 octane and then use the 10-15% ethanol to boost the octane ratings up to that 87 or 88 figure at the pump.

Now that turbocharged engines are becoming the majority, we ought to be having a nationwide push to make 89-90 octane the new "regular" unleaded rating and having 92-93 octane as premium fuel. We could have turbocharged gasoline engines running higher compression ratios and higher boost levels to achieve better fuel economy. It would be a nationwide benefit to do this.


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## 6speedTi (May 18, 2018)

Many countries worldwide offer one grade of gasoline. Some with and without ethanol. Each country has their own regulations. You make a valid point. Gasoline in countries that offer one grade have a octane ratio of 91 US or 95 RON European. So 91 octane US is premium grade. Anything above that is considered super or super premium. So if you have a vehicle in the US that calls for premium fuel then that's referring to 91 octane. My motorcycle calls for premium grade and specifically states 91 octane because it has a 12:1 compression ratio. My Honda S2000 also calls for premium grade. I don't know the compression ratio but I would guess it's also 12:1. There are other factors that you should consider in choosing the correct octane rating for your vehicle. Turbo or Super charged, seasonal temperatures and altitudes.


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## jblackburn (Apr 14, 2012)

Tried it a handful of times, and I think it runs smoother on 93E10 than 91E0. MPG was about the same too.

Anecdotal though: our naturally-aspirated VW does ~3 MPG better highway on the stuff when we've used it on the same trip vs the 89 it's usually fed. Could be octane difference, could be lack of ethanol.


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## 93bandit (Mar 2, 2020)

jblackburn said:


> Anecdotal though: our naturally-aspirated VW does ~3 MPG better highway on the stuff when we've used it on the same trip vs the 89 it's usually fed. Could be octane difference, could be lack of ethanol.


I would argue it's the lack of ethanol. Gasoline has more BTUs per gallon than ethanol. Thats the main reason ethanol nets lower MPG than gasoline. Octane has little to no effect on fuel economy.


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## jblackburn (Apr 14, 2012)

93bandit said:


> I would argue it's the lack of ethanol. Gasoline has more BTUs per gallon than ethanol. Thats the main reason ethanol nets lower MPG than gasoline. Octane has little to no effect on fuel economy.


Unless it's tripping over the knock sensor constantly (usually turbo motors like the Cruze). I don't think this one is on 89, although it does lack low end grunt on 87 that it gets back on 89+


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## 6speedTi (May 18, 2018)

Just my opinion. If your running a boosted engine you should up the octane rating. 89 is a good start but I would run 91 if you can find it. What I mean is many fueling stations have 89 or 93. New engines have so much technology that many will argue that the manufacturer says to use 87. True but they want you to keep costs down to make sales. Behind the scenes under the hood those sensors are compensating for the lower performing 87 octane fuel.


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## Barry Allen (Apr 18, 2018)

93bandit said:


> Octane has little to no effect on fuel economy.


In extremely limited circumstances for naturally aspirated engines, it does. I have a friend (former coworker) with a Dodge Ram 2500. The V-10 engine is his pickup required premium if it's doing heavy towing. Mid-grade is OK the rest of the time.


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## 93bandit (Mar 2, 2020)

jblackburn said:


> Unless it's tripping over the knock sensor constantly (usually turbo motors like the Cruze). I don't think this one is on 89, although it does lack low end grunt on 87 that it gets back on 89+


Yes, tripping over the knock sensor will affect fuel economy, but thats only an indirect effect. Octane itself isn't causing lower economy, the ECUs reaction to SPI is. But, I get your point.


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## 93bandit (Mar 2, 2020)

Barry Allen said:


> In extremely limited circumstances for naturally aspirated engines, it does. I have a friend (former coworker) with a Dodge Ram 2500. The V-10 engine is his pickup required premium if it's doing heavy towing. Mid-grade is OK the rest of the time.


When the truck is towing, it's under extreme load so it's more likely to experience SPI. It's the same as an engine that doesn't knock under 1/2 throttle but the same engine will knock if under WOT. Increase in load can contribute to detonation.


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## Barry Allen (Apr 18, 2018)

93bandit said:


> When the truck is towing, it's under extreme load so it's more likely to experience SPI.


This truck is a 2003 Ram 2500 with the Magnum V-10. That new generation of truck switched the air box to the passenger side and the V-10 engine has the intake manifold with the throttle body on the driver side. Dodge didn't want to make any expensive changes to the intake manifold, so their solution was a pipe that runs across the top front of the engine compartment between the manifold and the radiator, does a U-turn, and goes into the throttle body. The result is when doing heavy towing, the pipe is exposed to high under-hood temperatures from hot air flowing out of the radiator. The result is absolutely atrocious fuel economy when towing because the engine is running rich to try to avoid detonation. Think of the torture those catalytic converters go through with that excess fuel!

Our solution was to take a junkyard hood, cut a hole in it, and weld up a sort of "corral" to have cold air flowing into a shorty cone air filter put right on the opening of the throttle body. Then we welded up a small hood scoop to bring in fresh, cold air and bathe that air filter and throttle body in cooler air.

The end result put fuel economy back where it should be. The engine was rated for 89 octane unleaded, but when towing anything really heavy he runs 91-93 octane.


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## nathanroe72 (Nov 25, 2016)

I tried some 91 ethanol-free fuel last fall but it didn't really seem to have any effect other than the mpg went up slightly.

This summer I've been running about a 50/50 blend of e85 and 93, give or take. Mileage dropped to about 20-25mpg where I was getting about 30-35mpg. We were having some really warm weather (90+ degrees) and driving home in the evening, the car was pulling a lot of timing because it was so hot. Blending in some ethanol between 30-50% made a huge difference. My car isn't tuned to run on it, but it is adding about ~15% to the fuel trim so it is 'safe' in that regard.


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## Snipesy (Dec 7, 2015)

nathanroe72 said:


> I tried some 91 ethanol-free fuel last fall but it didn't really seem to have any effect other than the mpg went up slightly.
> 
> This summer I've been running about a 50/50 blend of e85 and 93, give or take. Mileage dropped to about 20-25mpg where I was getting about 30-35mpg. We were having some really warm weather (90+ degrees) and driving home in the evening, the car was pulling a lot of timing because it was so hot. Blending in some ethanol between 30-50% made a huge difference. My car isn't tuned to run on it, but it is adding about ~15% to the fuel trim so it is 'safe' in that regard.


You can really mess with emissions doing that.

But yes most GM gassers the past 10 years are stock ready for E100. Just lack the sensor and programming.


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## nathanroe72 (Nov 25, 2016)

Snipesy said:


> You can really mess with emissions doing that.
> 
> But yes most GM gassers the past 10 years are stock ready for E100. Just lack the sensor and programming.


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## Snipesy (Dec 7, 2015)

nathanroe72 said:


> View attachment 288446


No one cares about gas engine emissions unless they smell. So why not?


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## kenm4670 (Jul 30, 2019)

Barry Allen said:


> For Cruze owners with the gasoline engine, does ethanol-free premium fuel perform better in terms of economy and power? I'm just curious of other's experience.


I would think the cost of premium fuel would the thought of premium fuel. Follow the owners manual recommendation. They is no increase in power or economy by using premium.


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## jblackburn (Apr 14, 2012)

kenm4670 said:


> Follow the owners manual recommendation. They is no increase in power or economy by using premium.


The owners manual makes no such claim.

They RECOMMEND 87 because it's the industry standard for non-luxury cars.


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## Diamond193 (Jul 28, 2019)

jblackburn said:


> The owners manual makes no such claim.
> 
> They RECOMMEND 87 because it's the industry standard for non-luxury cars.


If they recommended premium fuel I doubt very many people would have bought the car. Theyd rather get bye on whats the cheapest rather then whats the best.


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## Iamantman (Sep 24, 2018)

Diamond193 said:


> If they recommended premium fuel I doubt very many people would have bought the car. Theyd rather get bye on whats the cheapest rather then whats the best.


Yeah that's why he highlighted recommended. It's no secret 87 is recommended. Everyone has the same owners manual here. But there is metric tons of this info online. It's not a conspiracy theory. You can run 87 all day long and the car will be fine, just slower and get worse mpg. That's just the way the cookie crumbles. With most cars that's not really an issue and most people probably might not even notice, but because we've got turbos, it's especially beneficial to run higher octane if you can swing it.


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## Diamond193 (Jul 28, 2019)

Iamantman said:


> Yeah that's why he highlighted recommended. It's no secret 87 is recommended. Everyone has the same owners manual here. But there is metric tons of this info online. It's not a conspiracy theory. You can run 87 all day long and the car will be fine, just slower and get worse mpg. That's just the way the cookie crumbles. With most cars that's not really an issue and most people probably might not even notice, but because we've got turbos, it's especially beneficial to run higher octane if you can swing it.


I switched to vpower about 2 weeks ago and I think im gonna stick with that.


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## 93bandit (Mar 2, 2020)

Iamantman said:


> Yeah that's why he highlighted recommended. It's no secret 87 is recommended. Everyone has the same owners manual here. But there is metric tons of this info online. It's not a conspiracy theory. You can run 87 all day long and the car will be fine, *just slower and get worse mpg*. That's just the way the cookie crumbles. With most cars that's not really an issue and most people probably might not even notice, but because we've got turbos, it's especially beneficial to run higher octane if you can swing it.


I don't have time slips or way to accurately measure performance, so I just rely on the butt-dyno. I haven't calibrated it in a while, but I ran 87 for the first 40k miles and now have been running 93 for the last 10k miles. I have noticed it is less stumbly under acceleration, but I'd be hard pressed to say it's faster. Yes, on paper it should be since I'm using higher octane which allows more aggressive ignition timing, but in the real world it's not very noticeable. Also, I've hand calculated and recorded fuel economy for every single tank since I purchased the car with 38 miles on it, and have noticed no increase in fuel economy averages when switching to 93 octane. Fuel economy does go up and down with seasons and varies depending on whether I'm commuting or took a long highway trip, but I cannot positively confirm I get better fuel economy on 93. I live in SE MI so summer weather is fairly mild and winters are pretty cold. Maybe someone who lives in a hotter climate would noticed a bigger difference, but I have not. The only benefit I can see with running 93 is reducing the chances of piston failure. Other than that, I don't think the cost in fuel verses fuel economy increase is worth it.


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## jblackburn (Apr 14, 2012)

Diamond193 said:


> If they recommended premium fuel I doubt very many people would have bought the car. Theyd rather get bye on whats the cheapest rather then whats the best.


I was kinda hoping direct injection would help it run 87-89 better than the Gen 1 motors that were constantly tripping over the knock sensor. Power/pickup is better from a stop and low RPM, but I still feel they're very lumpy and inconsistent on lower octane.

There were a few times early on when I'd been running lower octane and dealer oil that I got on it moderately hard to merge and it would suddenly cough and then cut ALL power around 3500 RPM before ramping it back up - some kind of knock event, I'd guess.



> I have noticed it is less stumbly under acceleration, but I'd be hard pressed to say it's faster. Yes, on paper it should be since I'm using higher octane which allows more aggressive ignition timing, but in the real world it's not very noticeable. Also, I've hand calculated and recorded fuel economy for every single tank since I purchased the car with 38 miles on it, and have noticed no increase in fuel economy averages when switching to 93 octane.


I would agree that I haven't noticed much of a difference in fuel economy (if there is, it's <2 MPG, which is easy tank-to-tank variance anyway). 

Here in Virginia where I'm blasting the AC half the year, there is a HUGE difference in summertime response below 3000 RPM. 

Mine is the first of the Gen 2 though, so it's possible that GM improved their programming over time - they certainly tweaked the later Gen 1's to run better on 87 oct from my time spent in rental Cruzens.


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## 93bandit (Mar 2, 2020)

In case no one believes me, here's a graph of my fuel economy since I purchased my Cruze. I bought it new in July of 17 with 38 miles on it. It's a 2017 Hatch RS with the LE2 and M32 trans. I've used top tier fuel 95% of the time. My driving is about 75% highway, 25% city and I drive it easy. I use cruise control whenever possible, and usually drive 75-80mph on the highway. I used 87 octane from the day I bought it up to 5/31/2020. I marked on the graph where I started using 93 octane. I mentioned previously I've been using 93 for the last 10k miles, I was wrong. It's been about 5k miles. I tried to hand calculate economy every time, but there are a few outliers which I suspect I used the trip odometer MPG number on the high ones since it's usually optimistic. The few very low MPG numbers are likely do to extended idle and a few spirited drives with low mile fill-up intervals. I've also maintained 35-40 psi in all my tires. I'm the only one who ever drives the car, so there aren't many variables. You can see the economy trends throughout the year. Lower economy in the cooler months, better in the warmer months. Note the graph is less dramatic from 10/19 through today, that's because I've been driving a lot less than I used to due to COVID.


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## snowwy66 (Nov 5, 2017)

87 octane has been the recommendation since the beginning. Long before gas became unleaded.

I haven't seen any performance boost. My economy went up for the first tank and a half. The second half has dropped lower then average. 

Our Ethanol is 88.


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## Barry Allen (Apr 18, 2018)

jblackburn said:


> Mine is the first of the Gen 2 though, so it's possible that GM improved their programming over time - they certainly tweaked the later Gen 1's to run better on 87 oct from my time spent in rental Cruzens.


With that cracked piston service bulletin, doesn't GM recommend an ECU update as part of the repair? Has your car ever had that ECU update?


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## jblackburn (Apr 14, 2012)

Barry Allen said:


> With that cracked piston service bulletin, doesn't GM recommend an ECU update as part of the repair? Has your car ever had that ECU update?


Yes, probably to change the transmission programming so it doesn't try to lug up a hill at 1100 RPM in 5th gear. Peak LSPI territory.

No, it hasn't had it - or a cracked piston yet. If it hasn't blown up as I approach the end of my warranty, I might consider taking it in and having the update done out of my own $.


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## Barry Allen (Apr 18, 2018)

jblackburn said:


> If it hasn't blown up as I approach the end of my warranty, I might consider taking it in and having the update done out of my own $.


Maybe it's money better spent upgrading to an aftermarket tune? If your warranty is gone either way, go with the option for more power.


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## Taxman (Aug 10, 2017)

Snipesy said:


> You can really mess with emissions doing that.


So what happens to the E10-E15 emissions system when you try to mix E30 in the tank?


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## Barry Allen (Apr 18, 2018)

Taxman said:


> So what happens to the E10-E15 emissions system when you try to mix E30 in the tank?


Nothing happens. I owned a 2009 Hyundai Accent and I routinely filled it with E30. Filling it with E50 would illuminated the CEL, but it would run fine on E30. Fuel economy was down by about 5% but the cost of E30 was about a 20% discount from regular unleaded, so it was a net cost saving to me.

All gasoline engines use the O2 sensor in the exhaust to monitor and adjust the air/fuel ratio. Putting some ethanol in it will lean out the mixture a bit, so the ECU will adjust by injecting slightly more fuel. It does perform some checks to make sure the O2 sensor is performing properly. When I used E50 that was apparently outside the bounds of the ECU programming, and it assumed the O2 sensor was malfunctioning. Using E30 kept it within the limits of programming and the car would run fine.


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## Taxman (Aug 10, 2017)

I figured it was around 45-50% Ethanol when my 2007 Ion 2.2 would start to throw lean CELs. I only played with that for about a month when a local station started selling E85. I started by putting two gallons of E85 in it and filling with E10, then a few days later I'd add another two gallons of E85, then when it started throwing CELs I'd fill it up with E10 to make the errors go away. It always ran fine, it's just that when long term fuel trim got over +25, the ECU decided that something must be wrong and warned me about it.


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## Snipesy (Dec 7, 2015)

Taxman said:


> So what happens to the E10-E15 emissions system when you try to mix E30 in the tank?


The ECM is unable to compensate enough for E30. Well maybe it can. I don’t know really. But that’s the biggest concern.

I am sure the engine itself will run fine but the catalyst will heat up too slow due to the lean condition. That creates emissions.

Again to what extent if a problem E30 causes there I don’t know. As long as the catalyst heats up fine there is no big limiting factor. Could you run some more optimal timing? Probably. But it’s a minor difference.


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## Barry Allen (Apr 18, 2018)

Snipesy said:


> I am sure the engine itself will run fine but the catalyst will heat up too slow due to the lean condition.


The ECU is increasing injection pulse width to add more fuel to compensate for the lean readings from the O2 sensor. It does this up to a certain point and when it reaches the point that it's outside what the ECU is programmed to do, it throws a CEL because it assumes the O2 sensor is bad.


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## pandrad61 (Jul 8, 2015)

I’m diesel so can’t say but on my Motorcycle I only run non ethanol. When the weeks come I can’t ride as often it’s way way less likely to absorb moisture and rust my tank. Our 16 spark 1.4NA doesn’t seem to notice a difference.


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## Ma v e n (Oct 8, 2018)

The spark doesn't care as much as the Cruze because it's not turbo, and it's not direct injection.


Ignore me, Sorry thought this was a different thread


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## Barry Allen (Apr 18, 2018)

pandrad61 said:


> on my Motorcycle I only run non ethanol


My motorcycle is a BMW K100RS. It takes leaded fuel so I run 100LL from the airport.


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## Snipesy (Dec 7, 2015)

Barry Allen said:


> The ECU is increasing injection pulse width to add more fuel to compensate for the lean readings from the O2 sensor. It does this up to a certain point and when it reaches the point that it's outside what the ECU is programmed to do, it throws a CEL because it assumes the O2 sensor is bad.



Assuming you get that far. It takes time for the o2 sensor to warm up.

So before the the trim the ECM just has to assume. Shouldn’t really be a problem except for idling.... Idling is notoriously the bare minimum fuel possible. Well that doesn’t really work with E85. So it may sputter, or even stall out entirely. Which one the Cruze does, I am not sure.

Normal driving is more or less fine... More fuel can be managed just by pressing the accelerator a bit more and honestly you probably wouldn’t even notice a difference.... Until you pull to a stop anyway. Obviously lambdas will be all over but it’s not really that insane.


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## pandrad61 (Jul 8, 2015)

Ma v e n said:


> The spark doesn't care as much as the Cruze because it's not turbo, and it's not direct injection.
> 
> 
> Ignore me, Sorry thought this was a different thread


Yah the 1.4na isn’t picky in the least. We have had great reliability in its 30k since new. Our problems have been for and finish like snapped visors, rear wiper hoses leaking water inside.


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## pandrad61 (Jul 8, 2015)

Barry Allen said:


> My motorcycle is a BMW K100RS. It takes leaded fuel so I run 100LL from the airport.


I ride a fjr1300 but those boxer 4 always had me interested as a kid. Leaded fuel? Didn’t the EPA ban that’s tuff way before I was even born.


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## Barry Allen (Apr 18, 2018)

Snipesy said:


> Assuming you get that far. It takes time for the o2 sensor to warm up.
> 
> So before the the trim the ECM just has to assume. Shouldn’t really be a problem except for idling.... Idling is notoriously the bare minimum fuel possible. Well that doesn’t really work with E85. So it may sputter, or even stall out entirely. Which one the Cruze does, I am not sure.


On a cold start the ECU is running things rich just for the reason that the O2 sensor isn't up to temp. It's rich enough that E10, E15, E30, and probably even E50 will run fine. It will be more lean that the ECU blindly expects (because it's tuned for "rich" on E0 or E10, and the AFR will be leaner than expected but still rich enough to run).

Modern O2 sensors are heated to bring them up to temperature within a couple minutes. Start the car and the sensor is heating itself. Drive it (gently) and it's heating even faster. I can't say a specific time for each temperature, but modern O2 sensors are probably up to temp and functioning within 2-3 minutes of starting.


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## Barry Allen (Apr 18, 2018)

pandrad61 said:


> Leaded fuel? Didn’t the EPA ban that’s tuff way before I was even born.


Nope. It was finally phased out in 1996 in the USA (a few years earlier in California). I can remember leaded gasoline when I was a child in the 1980s, but it was being phased out somewhat quickly.

I don't remember when cars were required to use unleaded fuel, but my motorcycle is a 1985 model and that engine still used leaded gasoline.

I purchase 100LL fuel from the airport in a 5-gallon-jug and pour about 1 gallon into the tank before topping the rest off with unleaded. I don't know how much lead that puts in the tank, but I am trying to put _SOME_ lead in there for the valves while mostly using premium unleaded for the rest of the fuel mixture.


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## Barry Allen (Apr 18, 2018)

pandrad61 said:


> those boxer 4


The engine is an inline-4.


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## pandrad61 (Jul 8, 2015)

Barry Allen said:


> The engine is an inline-4.


Inline 4? Darn must have remembered that article wrong. That’s a shame I love the idea of a boxer 4 bmw.


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## Ma v e n (Oct 8, 2018)

HO2S are probably heated up and vehicle in closed loop within 90 seconds. I'll check next time I get a chance.


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## Taxman (Aug 10, 2017)

Barry Allen said:


> I don't remember when cars were required to use unleaded fuel, but my motorcycle is a 1985 model and that engine still used leaded gasoline.
> 
> I purchase 100LL fuel from the airport in a 5-gallon-jug and pour about 1 gallon into the tank before topping the rest off with unleaded. I don't know how much lead that puts in the tank, but I am trying to put _SOME_ lead in there for the valves while mostly using premium unleaded for the rest of the fuel mixture.


Most US cars got catalytic converters around 1976, I can specifically remember that my 1977 Saab was the last to not have catalyst (Bosch K-Jetronic mechanical continuous injection and air injection in the exhaust). 1978 US market Saabs had KE-Jetronic with oxygen sensor and a catalytic converter. 

From what I can remember, 100 Low Lead Avgas has about twice as much lead as auto gas was allowed in the late 1980s (cars were allowed quite a bit more before EPA regs). I can remember putting 89 octane Regular in the Saab around 1986-1987, but think it pretty much disappeared by 1989. I thought the 89 octane leaded Regular pumps were replaced by 93 octane Premium Unleaded pumps, but my mom can remember putting Premium Unleaded in her car in the 1970s (1977 Nova, 250 single barrel, would diesel like crazy if you ran it on 87 octane).


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## snowwy66 (Nov 5, 2017)

Barry Allen said:


> My motorcycle is a BMW K100RS. It takes leaded fuel so I run 100LL from the airport.


Is your bike older then 96?

That's when leaded gas was banned.

NM. Saw your post.


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## snowwy66 (Nov 5, 2017)

I had a 78 vw rabbit I think it was.

It had mechanical fuel injection but I don't recall it having a cat. I could be wrong.


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## Barry Allen (Apr 18, 2018)

snowwy66 said:


> Is your bike older then 96?
> 
> That's when leaded gas was banned.


Leaded gasoline lasted long enough for the majority of the vehicle fleet to turn over and use unleaded fuel. I don't recall the last time I saw leaded gasoline available at an auto pump (other than 100 octane racing gasoline sold at one fuel station along I-55, but it's been a few years and that fuel was $6.99 a gallon!) but it must have been when I was a child in the 80s.

The motorcycle certainly calls for leaded fuel in the owner's manual. Other message boards recommend using at least one tank of leaded fuel about every 3-4 tanks of fuel. Others also say it doesn't matter and just use unleaded. I never wanted to have any major engine trouble with the bike so I blend 100LL from the airport to at least feed it some leaded fuel on a regular basis. I figure that one gallon has more than twice the amount of lead that was allowable in auto fuel, so it's diluted to an acceptable level that will keep the valves seats lubricated properly.

Mine is an early 1985 model with the frame number prior to the introduction of hardened valve seats:


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## snowwy66 (Nov 5, 2017)

Today's gas is formulated for yesterday's vehicles. It had to be as people still drive around old vehicles.

Think studebakers. And older. So. There's no reason to be fueling with your concoction. Your bike is taken care of.

I started off with a 1982 yamaha 650. Ran leaded gasoline till it wouldn't run anymore. Dealer told me to use unleaded gas. The motor had carbon buildup. Leaded gas was worth then what you all consider carbon these days. Running unleaded got that motor purring again. 

I wouldn't worry about trying to find something. Your bike will survive.


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## Taxman (Aug 10, 2017)

snowwy66 said:


> I had a 78 vw rabbit I think it was.
> 
> It had mechanical fuel injection but I don't recall it having a cat. I could be wrong.



I don't know about catalyst, but I can confirm that a friend's 1978 had plain K-Jetronic CIS, not the feedback KE-Jetronic. When his cold start valve died and the car was pretty much worn out and worthless, I gave him a 3mm allen wrench and showed him how to adjust the fuel mix via the airflow sensor.


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## jblackburn (Apr 14, 2012)

Taxman said:


> Most US cars got catalytic converters around 1976, I can specifically remember that my 1977 Saab was the last to not have catalyst (Bosch K-Jetronic mechanical continuous injection and air injection in the exhaust). 1978 US market Saabs had KE-Jetronic with oxygen sensor and a catalytic converter.
> 
> From what I can remember, 100 Low Lead Avgas has about twice as much lead as auto gas was allowed in the late 1980s (cars were allowed quite a bit more before EPA regs). I can remember putting 89 octane Regular in the Saab around 1986-1987, but think it pretty much disappeared by 1989. I thought the 89 octane leaded Regular pumps were replaced by 93 octane Premium Unleaded pumps, but my mom can remember putting Premium Unleaded in her car in the 1970s (1977 Nova, 250 single barrel, would diesel like crazy if you ran it on 87 octane).


Loved my Saab (85 8V with all of maybe 60 HP left in it)- it was a part of my life for 20 years. But man the K-Jet system was a freaking piece of crap as it aged.


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