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Why Do We Still Use Gasoline?

Fed-Up-With-Fuel-Price-Whining asks: "Why are people still looking toward the gasoline companies for fuel? Is it because gasoline in a combustion engine is the most efficient, or is it because oil companies buy off the efforts of other possiable fuels? Fuel cells are a much better and cleaner way to use the fuel and there are other fuels out there with MUCH better potential than gasoline. Why don't people stop their crying and answer the oil companies jacking up of prices by converting their cars to other fuels?" Good question. The problem for most of us, I think, is availability. You mention Arizona, USA but what about the other American states? If something like this could be done here in good ole Virginia, I'd happily switch, assuming there existed a decent number of places to refuel. Honestly, if this were to be a reality for the states, alternate fuel sources and the infrastructure to support them would have to evolve pretty much simultaneosly. What do you think?

"Here in Arizona it costs around $6000 to convert your car to natural gas. If you do it Arizona will PAY the $6000 to convert the car. If you buy more than $280.00 a year in gas you will not have to pay for taxes or registration of your car.

I don't know, it just seems like a MAJOR buy off by the oil companies, the gas stations, and politicians. I know for FACT in Brazil you are able to buy a car which burns gasoline or methonol. And the Gas Stations have BOTH gasoline and methanol pumps. The methanol cars are still combustion engines.

There is one problem I know of methanol based cars. They are more like diesel engines. They are hard to start in COLD weather. But if they were converted from combustion to fuel cell based they would be even more efficient and much cleaner burning."

19 of 940 comments (clear)

  1. Re:Part of the problem is Infrastructure by Zachary+Kessin · · Score: 4
    There is a limit to how efficient you can make a reciprocating engine. An electric power plant is probably about 90% efficient, but it does not have to go anywhere. The engine in your car has to work across a wide range of conditions, reliably, be started up and shut down repeatedly, and by small and light enough to fit in your car.

    Jet Turbine engines tend to me more effient than piston engines, but tend to be rather large.

    The Cure of the ills of Democracy is more Democracy.

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  2. Who says the problem is gasoline/petrolium? by jd · · Score: 4
    When you get right down to it, this is not as tennable argument as it first appears. Shell Oils runs a yearly fuel efficiency race. The only power supply the cars can have is standard petrolium. The cars manage over 10,000 miles to the gallon.

    Sure, the acceleration isn't great, and these are not going to win any Formula 1 races in the near future, but think of it this way. The people who buy the cheapest, dirtiest, least-efficient, oil burning cars are your OAPs and students. OAPs are not the sort of crowd who go out-dragging the local chapter of Hell's Angels - they're more likely to be stuck in heavy traffic, crawling to and from the stores, hoping that their morning trip won't take until nightfall.

    Students, likewise, are more likely to be driving to and from lectures. Cross-country trips are less than likely, and hauling ultra-heavy loads are unlikely to be regular events.

    If someone were to build disposable cars, designed to last 3-4 years, using this ultra-efficient technology, you could throw away a good percentage of the gas-guzzlers. Less gasoline requied = more gasoline to go round.

    As trends tend to catch on, especially really weird ones, something like this could utterly crush the SUV market (another horrible bleeder of the world's resources), and lead to people wanting to buy efficient for a change.

    I can't blame the markets for pandering to demand. They're there to make money, not save the world. If most people want to turn precious reserves into pollutants, for no good reason, then the markets will respond and provide the means to do so.

    Changing the fuel won't change the result. Only changing the attitudes can do that.

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  3. Why ICE's are so inefficient by Fandango · · Score: 4
    The EPA has a great site here that covers all aspects of fuel economy and includes some really handy CGI's to let you compare different 1985-2000 cars for fuel economy.

    On this site, you can also find this handy chart which shows visually exactly why ICE's are so inefficient.

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    Jake

  4. How about air (yes air) by getafix · · Score: 4

    Check out Zero pollution
    Apparently the Mexican govt has ordered 1000's of these to replace taxis.

  5. Gas is too advanced to be beat 10x by Sangui5 · · Score: 4

    There's an old adage that in order to convince people to switch from an entrenched standard, you have to be 10x better. The infrastructure behind gasoline is extensive, and despite the technological deficiencies of gas, economically it is the cheapest way to get around.

    The only way to make the alternatives that much better is to make gas worse.

    Tax gas. Tax inefficient cars. Raise the pollution controlls on _gas_ powered vehicles through the roof.

    You may think that this will hurt people and drive up prices. It may drive up the price of gasoline, and the price of driving around, but if you do it right, you can keep the cost of living about the same. Remember, the more expensive it is to drive around burning gasoline, the less gasoline will be burnt. The gas we burn, the less crude oil goes into its production. And the more crude we have, the cheaper we can make diesel, kerosene, plastics, etc. Artificially expensive gas means cheaper frieght charges (cheap diesel), cheap power (cheap crude/kerosene), and cheap consumer goods (plastics and other petrochemicals).

    Of course, this would still look bad politically, but you can balance that out by putting all those tax revenues towards gas price relief for poor people, tax credits for efficient cars, etc. It would also (possibly) have the effect of breaking up OPEC. If demand falls, the marginal OPEC members (Veneualia (sp?) et. al.) will almost be forced to cheat on their quotas to make ends meet. And once enough of the small ones start cheating, the rest will follow suit, cutting the price of diesel/electicity/plastics/whatever even further.

    If you are careful to balance the effects against each other, you can have your alternative fuels/low pollution without fscking everybody over.

  6. Re:What are you talking about by Parity · · Score: 4

    They could construct it--but why? People "outside of cities" by definition have low population densities. "Mass" transit requires high populations.

    This is simple overgeneralization; there are -many- places with the population density to support mass transit that don't have it - namely, just about every suburb. Presumably you'd run the busses infrequently and down only the major roads, but it'd be -something-.

    Before you say it can't be done, consider the Sili Valley - despite the complaints about the efficiency or lack thereof and whether light rail is a waste of time, etc, there -is- a mass transit that runs all up and down and through the suburbs and shows no sign of vanishing. You can take the bus, the light rail, or the cal-train to various destinations, and at the other end take something else.

    By contrast, in the Boston area, and most cities east of the rockies, -only- the metro region has mass transit, and the suburbs are left to hang. Or, (using the Boston area as an example) you have transit into the city with peripheral parking lots but no transit -out- of the city. In case nobody noticed, the high tech industry (and others that can manage it) are slipping out of the cities and building up along the highways that run out of them. I live -in- the city and work -outside- it, and the reverse commute is really only doable by car... it doesn't do me any good to be left in a 'commuter parking lot' with a residents-only sticker-required no-overnight-parking lot. I could, conceivably, even leave my car in the parking lot overnight and do -most- of my commute by transit and the transit-less leg by car, but the policies are set up to discourage it.

    Anyway, the real reason there's no mass transit in the suburbs is because people in the suburbs don't want those icky 'city people' (read, minorities) coming out to shop in their nice isolated suburban shopping districts. Which, admittedly, they would probably do, but so what? Seeing a black face or hearing a conversation in portuguese isn't going to kill even the most whitebread of the suburb dwellers. (If you think I'm just trolling/flamebaiting, check out the zoning laws & transit-related votes in a suburb near you...)

    Parity None


    --Parity

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    --Parity
    'Card carrying' member of the EFF.
  7. Re:Gasoline Bites, Cars Bite by paul7e · · Score: 4

    >> when one can have a spacious house on several >> acres of peaceful, clean air, life-producing >> fields where nobody gets in your face?

    So let me review: you boast about enjoy the "clean air" while you pump 30 miles a day worth of crap into the atmosphere from your car?

    Do you see a possible logical disconnect here?

    If you're driving towards a major city on your commute, you're making the air worse for the city folk, who are perhaps NOT using their cars. Urban sprawl is a problem, and the attitide that "the city's problems aren't my problems" ain't gonna make things better.

    paul

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  8. You are a couple years late by FascDot+Killed+My+Pr · · Score: 4

    You can already buy half-electric cars from major manufacturers. Honda and Toyota both came out with hybrid cars this year. Check out the "Insight" and the "Prius".
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  9. Re:I'd do it by Izaak · · Score: 4
    Find a solution that will not result in hundreds of thousands of people being laid off. Find a way that will not result in the economies of several countries being tossed down the toilet which will further result in war, unrest and more people suffering not to mention economic problems for the rest of the world.

    But of course any alternative would take time to phase in. Loss of profits and job cutbacks in the oil industry would be gradual. The people leaving the oil industry could find jobs in the new markets created by the oil alternatives. The oil companies would have plenty of time to diversify into new markets. 'Protecting Jobs' is never a good argument for holding back a better technology.

    Thad

  10. I have an Insight by FreakBoy · · Score: 4

    I bought one back in April. I can get over 80mpg on the highway (at about 60-65mph).
    City driving is another story. I don't drive to much in the city, but here in Chicago I "only" get 50mpg, not the 61 they claim. I'm certainly not complaining, but I wouldn't mind getting 60+ mpg in the city.

    Since I drive over 500 miles a week, I thought this would be the best choice for a new vehicle. :)

  11. The Engineering Perspective. by Life+Blood · · Score: 4

    Why do we still use gasoline instead of another power source? There are many reasons but here are a few:

    The chemical energy stored in gasoline is very high for its weight while still being easily accessible. Methane and ethanol all have less energy stored per unit weight. This means that cars powered by gasoline can out accelerate these alternative fuel cars because they can release the chemical energy faster and turn it into kinetic energy. They also have better range because they have smaller lighter fuel tanks which weigh less. In many alternative fuel cars you loose a lot of trunk space to the fuel tank.

    More energy per weight is diesel fuel. The problem here is that the energy is harder to release easily since diesel doesn't burn at room temperature at one atmosphere. This means the energy is harder to release and performance drops. Fuel efficiency is slightly better however.

    As for fuel cells, I think the big problem is that you lose performance again. They don't combust gasoline they release the energy using a different chemical reaction. It works more slowly but more uses all the energy more completely and produces less harmful by products. This is nice, but makes for lower performance.

    Electric cars are nice, but all the batteries are heavy and they take hours to recharge. You lose range and convenience. Hybrid cars are nicer because you power a set of batteries with a small gas engine. The batteries then power the wheels. Honda makes one of these I believe. The problem is that after two to three years you need a new set of batteries because current battery technology wears out too easily. And that many batteries are expensive.

    I've also heard of all kinds of wacky fuels like vegetable oil. The guy did this to his volkswagen and got the oil from local fast food places that usually have to pay to get rid of it. His car exhaust smelled like french fries. No sure why this caught on, probably because it was an obscure idea that isn't practical on the large scale.

    Basically what is preventing the widespread adoption of an alternative fuel is that nobody wants to loose anything. Nobody wants a slower car with shorter range. Nobody wants to pay more for such a car either. People also don't like to buy unproven technology. If you want an accepted alternative fuel car which is more efficient, buy a diesel.

    BTW has anyone done studies to see if, after the power loss in transmission of the electricity to the house and the loss in the car itself, electrically powered cars actually pollute less than gas. The engine is less efficient, the transmission of the power to the house loses efficiency, and the power plant creates pollution just like the car would. By advocating electric cars are we simply changing the location of the pollution instead of reducing they levels of it?

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  12. Re:Gasoline Bites, Cars Bite by dazedNconfuzed · · Score: 4
    Gee, nice that you have convenient public transportation.

    Some of us can't stand the sardine-can environment of the cities. Why rent an overpriced tiny box to live in, with the only view being of someone else's window? Why put up with noise, crime, expenses, dependency, panhandlers, wall-to-wall people, and government meddling...when one can have a spacious house on several acres of peaceful, clean air, life-producing fields where nobody gets in your face? Why live in total dependence when one can live in near-independence? That's just the rhetorical question to set up the response:

    I live in the country, about 30 miles from work. I need a car to get anywhere, and there's NO WAY that public transport would work: the density of people is just way too low to support it...and you'd need a car just to get to the bus stop. I pay less for the freedom to travel anywhere, anytime, without traffic jams, fast, in comfort and convenience, than you do to ride your when-and-where-it's-scheduled dirty sardine-can-on-wheels bus or subway.

    The better solution is: telecommuting. That way the pollution goes to almost zero.

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  13. oil should be kept for more important uses by asfasmcdas · · Score: 4

    One thing that seems to be forgotten in all these debates is how dependent we are for oil for other purposes. What is going to happen to the chemical and plastics industries - and indeed all the subsidiary industries that rely on their products once we run out of oil? We may well discover other sources of energy for transportation and heating - but there is no obvious substitute for the oil we require to manufacture the plastics we use. Just think of how prevalent plastics are today - just look at the big lump of plastic in front of you right now - and all the components under the hood that are keeping everything ticking over! If we waste all our oil resources on transportation and our technological civilization depends on oil derived plastics then how long can we survive with this level of technology? If we were a more responsible and mature society we would restrict our consumption so that future generations (and we should really be thinking way beyond our grandchildren) will enjoy some of the same resources we have today.

  14. Actually it is ENERGY DENSITY by Hasdi+Hashim · · Score: 5

    I work at Ford's Enviromental Vehicle project and i can't legally speak for them. Without trying to give out anything proprietary, in general, energy density is the real killer. 1 kg of gasoline efficiently tapped can give you 42-44 Megajoules. NiCad, Lead-Acid and Sodium-Sulfur of the same weight barely have a fraction of this energy. To replace 16 gallon (approx 42.39kg) of gasoline you need 14838.768 kg of lead acid battery. This is ten times the average weight of a car (around 1500kg). Since the car is 11 times heavier it should require 11 times more fuel. You do the math. It may more costly to your pocket and the enviroment (more energy use and heat dissipation).

    Ultracaps? That's great. I know one company that sells ultracaps with 10,850.69 Joules/kg. Packs a punch for your house intruder but can't you anywhere (literally).

    Ah.... somebody mentioned fuel cells. You can check out one of the suppliers ballard This is promising but the energy conversion unit is still heavy. Hydrogen actually packs more energy than gasoline: 38khw/kg (that's about 136.8 mejajoules/kg). Unfortunately, it hoards a lot of space. We could use methanol and carry methanol->hydrogen reformer that would take up more weight. After reliasing that the conversion unit takes more weight you begin to wonder, why don't you burn the hydrogen in the first place, instead of investing in the fuel cell stack, electric drivetrain and stuff? We are bothering with eletric motor? Why can't we just improve the efficiency of the internal combustion engine?

    Relative to electric motor, internal combustion engine (ICE) is highly inefficient. While good motor with a good controller can give you close to 95% efficiency, an ICE is at 17% in a good day. Worse it's peak efficiency is at certain torque and at certain speed. That is why we have gearbox system and clutch. When the car stops, you have supply it with some fuel to keep spinning (idling) which is 100% loss (0% efficient). With electric motor you can adjust your torque and speed electrically and reclaim energy in braking.

    I think I better stop here. in the meantime you are welcome to buy Ford electric bicycles and other stuff http://www.thinkmobility.com

    Hasdi
    Not speaking for Ford

  15. Interesting subject by TheCarp · · Score: 5

    I think the real problem is that Gas has been so cheap in the US for so long. We have had it WAY too good.

    Plentiful supply, no shortages, cheap prices. Hell yes I enjoy it too. Even today with higher prices, gas is still fairly cheap.

    Its cheap, its what we know. Whn the masses are confortable, there is no push to invest and research alternative fuels. Face it...any new system will need to be able to compete with the existing fuel infrastructure.

    As for alcohol based cars....you can make your own ethanol and use it to power your car...many engines will run without modification (tho not well...much better to use a gas/alcohol mix). You can even get a licence to distil your own ethanol for fuel really cheap from the BATF. (in the US obviously).

    Linday's Publications (http://www.lindsaybks.com) has a book on building a fuel alcohol still that talks about all this stuff. Really good book. Of course the MPG is less than Gas, but it burns ALOT cleaner....and thus keeps the engine cleaner.

    I am personally of the belief that there is alot of potential in these feilds. I would like to get a Gas/electric hybrid (the honda insight beats the pants off even my motorcycle for MPG) and see it modified to run off Ethanol or methanol....now that would truely be a great car.

    --
    "I opened my eyes, and everything went dark again"
  16. Infastructure/Price of Converting by Dungeon+Dweller · · Score: 5

    It will happen sooner or later with enough incetive, but right now, there is a strong infastructure built up in the support of gasoline automobiles, and not one in support of alternative fuels. There are also a wide variety of fuels, and people want cars that run THE NEXT FUEL, not just a cleaner fuel. Also, cost is a big factor, most states won't pay to have your car converted. Most people know how to work on/supe up gasoline powered cars. They don't want to take them in to a mechanic to work on them when they are used to working on them themselves. Mechanics are trained to work on gas powered cars. Companies manufacture mainly parts for gas powered cars. The infastructure to purchase fuel, inexpensively, for alternative fuel vehicles isn't everywhere.

    I mean, I would love to have an electric powered car, right? Where would I charge it? Just about only at my house! What would I charge it in? I plug that I have to get specially installed that is more powerful than the ones on my dryer, possibly requiring that I have lines run to my house for the power requirements.

    It's not like, "Why would anyone run open source software." When the infastructure is there, and in fact better than that of closed source software. This is something where you really have to use the options given to you.

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    Eh...
  17. Re:I'd do it by gwernol · · Score: 5

    If our province had that kind of incentive. Natural gas is much cleaner (and more efficient) than gasoline. The oil companies are a much greater monopoly than what Microsoft is, and everyone does complain.

    The parallel to Microsoft is interesting because, of course, the first major anti-trust breakup of a company was of Standard Oil in (I think) 1911. The government ruled them a monopoly and split them into a number of smaller companies, which were the forebears of the major oil companies we have today.

    The argument against the present oil companies is that they operate an informal cartel to keep prices up. This is one disadvantage of splitting a monopoly - it is much harder to show that a number of companies are colluding to act monopolisticaly, whereas its relatively easy to show that a single company is a monopoly. A two Microsoft cartel may be even worse than one Microsoft monopoly.

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  18. Re:I'd do it by thesparkle · · Score: 5

    "We need a way to show the oil companies that we're fed up of lining their pockets with cash."

    And we are fed up with them paying their employees and paying those taxes. Pesky jerks.

    Find a solution that will not result in hundreds of thousands of people being laid off. Find a way that will not result in the economies of several countries being tossed down the toilet which will further result in war, unrest and more people suffering not to mention economic problems for the rest of the world.

    Find a solution that when implemented, will be as cost affective as what it replaced. For instance, don't force everyone to buy a new car which costs two and a half times more than a gasoline powered device and then force them to use a fuel that costs several dollars a gallon and have that same device and fuel get the same mileage as their previous gasoline-powered device.

    These are just a few of the problems that enviromentalists and politicians usually don't address: What affect will this have on the working person in this country? Using the excuse "Well, it may cost you more, but we know what is best for you", will result in insurrection when deployed in this scale.

  19. Gasoline will be with us for some time yet. by BigBlockMopar · · Score: 5

    Gasoline is here for a while. There's just no good substitute for most people yet.

    Natural gas/Propane are both great, but the infrastructure to support them just isn't there. Gas stations would have to make a huge investment to be able to support them at all stations. It's great for fleet vehicles like taxis, since the cab seldom leaves its home city, and the driver can get to be very familiar with which gas stations have already added propane/NG fueling services.

    While gasoline is very nasty stuff, it's a little safer than carrying around a large tank of compressed and invisible fuel. A car accident that ruptures a full automotive propane/NG tank would be far more likely to be deadly than a car accident that ruptures a gasoline tank and causes a spill. Let alone the dangers of hydrogen as a fuel, which, like acetylene, sweats its way out of cast iron tanks.

    You'll note that most parking garages won't allow propane/NG vehicles. If, over the years, one of the fuel lines corrodes or develops metal fatigue cracks, a slow fuel leak could cause a parking garage explosion. Since parking garages tend to be under buildings, conceivably, the building could come down. Dire consequences? Yup. One in a million chance? Yup. But if there are millions of propane/NG vehicles out there, it's a bigger worry than gasoline.

    Gasoline tends to drip, and you can usually see a leak. You can always see a puddle. With invisible gases, that's not possible: you have to rely on the odor, which you might not catch if it's windy.

    Admittedly, conditions have to be just right for a propane/NG explosion, but it's unquestionably somewhat more dangerous than gasoline. Much like a Ford Pinto's gasoline tank is more dangerous than the average.

    Fuel cells are a great idea, and I'm sure they'll be with us in a few years. I've had the opportunity to drive a Ballard-powered golf cart, and it was a lot of fun. Silent, fast, much more efficient than an internal combustion engine. It was nice. But the problem is that fuel cells still require membranes that are as difficult and unreliable to mass produce as color LCD displays were a few years ago. In time, that will change.

    Fuel for fuel cells will still have to be something combustible. A fuel cell simply burns fuel through what is essentially a catalytic reaction, as opposed to a combustion reaction. So we're back at the same choices: drag around a tank of liquid gasoline/methanol/ethanol, or drag around a tank full of compressed hyrdrogen/propane/NG.

    Since the infrastructure already exists for the distribution of liquid fuels, you're probably still going to be pouring some sort of liquid fuel into your tank.

    Fuel cells, by virtue of their basic operation, will be very sensitive to impurities in the fuel. Deposits formed inside the fuel cell will require the replacement of the expensive membrane. A conventional paper fuel filter, like your car currently has, will not suffice. That's going to mean very expensive processes of lining tanks in every refinery, truck, gas station... which will be carried on to you, fair consumer.

    Electric cars are a great idea, but they're not practical for two big reasons.

    First things first, all batteries use a chemical reaction to convert chemical energy into electrical energy. The more efficient the battery, the more efficient (and therefore nasty) the chemicals must be. In order to achieve range in an electric car, every bit of free space is going to have to have batteries crammed into it.

    Now, what happens when you're involved in a fender-bender? A battery will probably rupture somewhere, spraying out strong acids or alkalines. Accident victims will often have chemical burns. And every last fender-bender on the Santa Monica Freeway would result in a Haz-Mat team cleaning up the road. As if gasoline wasn't hazardous enough.

    Electric cars also need fuel. The fuel, of course, will be electricity to recharge the batteries. If you're plugging your car in at night, your electric bill will go up. No big deal, it will probably be cheaper than gasoline. But what happens when the majority of the 6 million or so cars in LA are plugged in every night? The power from your wall outlets comes from somewhere... how many nuclear power plants will have to go up to deal with the increased electrical needs? How many more Hoover Dams will have to be built? Remember, tidal and solar power just aren't capable of serving any sort of electrical need yet. Building coal or other fossil-fuel powered plants just defeats the purpose of electric cars.

    What will your electric bill look like as the demand for electricity outstrips supply? It already does that every year just with air conditioners. Look at the situation in Montana at the moment.

    Add to that the fact that a modern gasoline car is about 70% efficient. Not good, right?

    Most electric distribution systems are only about 40-50% efficient. So, on a per car basis, you're already using more energy by running an electric car. Then consider that batteries are at best 70% efficient. While the car's electric motor itself may be upwards of 90% efficient, your efficiencies have already added up and negated any benefit.

    Gasoline is evil. Electricity is evil. Cars are evil. But they're here to stay; better just to continue to refine what we have. And when the fuel cell is ready for mass production, I'll happily fill my efficient fuel-cell powered vehicle up with renewable and clean methanol/ethanol.

    I know for FACT in Brazil you are able to buy a car which burns gasoline or methonol.

    Most American cars now will run very happily on either gasoline or methanol.

    Methanol is, of course, a form of alcohol, and has properties somewhat different from gasoline. For one thing, it's significantly more corrosive to some of the rubber and plastic parts in a car's fuel system. That has been addressed; for example, all new Chryslers since 1991 (correct me if I'm wrong) include fuel system components that are meant to handle it.

    Chrysler had a wonderful test car at about that time. It was a 1990 or 1991 Dodge Spirit R/T with a 2.2L or 2.5L engine - the same motor as most K-Cars, Dodge Shadows, etc. With very little work, they'd adapted the fuel system to happily take methanol/ethanol. And the fuel injection system (discussed below) was fitted with a fuel type sensor that would allow the car to run happily on any ratio of gasoline/ethanol/methanol.

    Combustion properties are quite different. Since methanol burns differently, if you were to just dump it into your gas tank, your engine would run.... sorta. But since your carburetor and ignition timing are calibrated for gasoline, it wouldn't run very well. Knocking, poor performance, poor gas mileage, and stinky tailpipe.

    Over the years, as the car makers have adopted electronic fuel injection systems, this has become less of a problem. EFI systems are meant to enhance driveability, gas mileage, performance and emissions by monitoring how the engine is behaving, and then adjusting fuel/air ratios and ignition timing accordingly. It's entirely a closed-loop, feedback oriented system.

    As a result, if the engine is knocking, for example, a sensor on the engine will detect it and the computer will retard the ignition timing until the knock is gone. If the oxygen sensor on your tailpipe is reading too much oxygen (ie. mixture too lean), it will add more fuel. If the O2 sensor reads no oxygen, it will assume the mixture is too rich and lean it out a little bit. This happens hundreds of times a second as you drive. In this way, the engine can adapt a great deal to the kind and quality of fuel being used, with the benefits of better performance and lower fuel consumption.

    And, if your oxygen sensor's (or any other sensor's) readings are way out of whack, the computer will realize it, and light up the "Check Engine" or "Service Engine Soon" light. At that point, the computer is making a best guess for how to run the engine, and while the car will still run, performance will not be optimal. If the car's engine can't cope with alternate fuels (ie. the computer isn't allowed enough range in its adjustments to timing and mixture) then this is probably what you'll see. And, likely, when you next fill it up with real gasoline, the little light will go out.

    Of course, if your Check Engine light doesn't go out, take the car to the dealer as soon as possible.

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