Want to save some gas? There’s a sucker born every minute!
When gas prices climb, the crazy people and swindlers come
out of the word work. Since we are well on our way towards gas prices going
above four dollars a gallon all across the country and not just on the coasts, consumers
are grasping at straws. They are doing anything they can to try and save fuel
including spending money on contraptions that come with big promises. Many
cheats, thieves, and charlatans are pushing all sorts of products to try and
tell you that you can save fuel by installing their revolutionary device.
Most of these devices are either doing something to change
airflow into the engine, or they are doing something to try and affect the
combustion process, or they try to enhance the ignition source. The devices
that change the airflow into the engine probably end up blocking the flow of
air into the engine more than anything else. This will actually lead to a loss
in power and possibly a decrease in fuel economy. The gadgets that claim to affect
combustion probably don’t do anything at all to the combustion process, and in
some cases might even be harmful to some of the things that make the vehicle
run right, such as O2 sensors. If the device adds any kind of fluid to the air
fuel mixture it is possible to hurt the O2 sensors which are installed in the
exhaust pipes.
They all claim an increase in fuel economy somewhere around
20 to 30 percent. The problem with this is that modern engine control systems
are so accurate and so efficient that only a tiny fraction of the fuel that is
injected doesn’t get consumed. When fuel is not fully burned in the combustion
chamber it comes out the exhaust as carbon monoxide and hydrocarbons. Looking
at the emissions from a modern vehicle, before the catalytic converter, the
amount of CO and HC’s is very low. CO is likely to be less than .009% and HC
levels will be less than 1 part per million. How on earth can it be possible to
increase your car’s fuel economy by 20% by burning this unburned fuel, when we
are only talking about the possibility of burning such a tiny amount?
Most of these devices take a theory that applies to
something else in the engine function or controls, and misapplies that theory
in the name of saving fuel. The following is a bit of information about a few
of these devices from different manufacturers. These are not necessarily the
most popular ones but they are representative of the different types of devices
that the consumer can waste their money on in a bout of wishful thinking.
Tornado Fuel Saver
This is a little device made from small metal fins arranged
together in a circle that are supposed to create a swirling motion in the
intake air. One of these contraptions will usually cost you about $50. This
swirling motion is supposed to increase volumetric efficiency or something like
that. The fact of the matter is that most engine designs and intake manifold
setups are already designed to create turbulence or a swirling motion in the
air stream that enters each cylinder. This helps to atomize the fuel as it
leaves the injectors and flows into the combustion chamber, and it is supposed
to help the fuel mixture fill the combustion chamber evenly so that it gets
burned more thoroughly.
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The Tornado installed |
Swirling the air as it enters the intake manifold is useless
since the air splits into the various intake ports as it goes into the engine
and how is it supposed to keep this swirl? Automotive engineers have been
studying air flow and volumetric efficiency for over a hundred years now and
they know what works and doesn’t work when it comes to making the air behave
properly in the intake manifolds and the combustion chamber. If efficiency
could be increased so easily every engine designer and manufacturer would immediately
be integrating their own version of this design or process into their product,
and if they didn’t it’s very likely that the EPA would mandate that they do so.
This notion really applies to all of the gas saver devices.
Platinum Gas Saver
This item will set you back about $150 plus installation. Many
companies build something along these lines; they are all about the same thing.
Manufacturers claim that it might take 1,500 miles before it starts to become
effective. This is another common claim from the people that make just about
every fuel saver. They also claim that you might need to replace your oxygen
sensors. This is silly because no good reason exists for doing so just because
you are now running tiny amounts of platinum through your engine. The real
reason that they recommend this is because most O2 sensors on cars that have
been on the road for a while, sat for 100k miles or so, probably have O2
sensors that have lost some efficiency anyway.
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Magic platinum fluid. If the solution in the bottle really is platinum, it can't be cheap. |
Any gas saver that uses platinum has some kind of reservoir
where a solution is held that contains some form platinum. A vacuum line from
the engine’s intake manifold connects to the reservoir where the solution is
sucked into the intake manifold. Once inside the manifold it goes into the
combustion chambers of the engine, or at least into the combustion chamber that
is closest to the vacuum line.
The theory is that when combustion takes place in the
presence of platinum, the combustion will be more complete. Platinum is one of
the elements found in catalytic converters to act as a catalyst to trigger the
complete oxidation of any of the carbon monoxide and hydrocarbons that didn’t
get used up in the combustion process. The definition of a catalyst is
something that triggers a chemical reaction but does not get consumed in the
process. Dribbling platinum into the intake manifold and then letting it run
down into the combustion chamber is not the same as coating a ceramic element
inside of a catalytic converter. This does nothing to save fuel.
Fuel Doctor
This device retails for $50 and is super easy to install
because you just have to plug it in to your cigarette lighter or accessory
socket. The device has a couple of LEDs that light up as you drive down the
road. The manufacturer claims that this electronic device cleans and conditions
the electrical power running through the vehicle’s electrical and electronic
systems as you drive. With this “conditioned” electricity the electronic
control systems become more efficient which helps the engine become more
efficient and thus use less fuel.
This is pure quackery and very insulting that these people
think we should believe this drivel! Conditioning the electrical power? What
nonsense! How is the condition of the electricity affecting engine output, and
how would something plugged into the power outlet change the electricity
flowing throughout all of the vehicles systems?
On their website they show a video of a power supply
attached to an oscilloscope and on the scope you can see some electrical noise.
They say that this noise represents the noise from the battery of the car. The
problem is that a DC battery doesn’t put out any noise, not even on a car that is
2 years old or older. This is just not true, and combined with the fact that
when your engine is running the system voltage comes from the alternator, their
demonstration is useless. Some noise can occur from the alternator but it doesn’t
have the effect on the computers and control systems that these people claim.
With the alternator turning typical electrical system
voltage is going to be in the neighborhood of 13.5 to 14.5 volts. The voltage
must be higher than the 12.6 volts of the battery so that electrons will flow
into the battery recharging it. The alternator actually produces 3 phase A/C
electricity but everything in the car runs off of D/C, and of course the
battery can only store D/C. Because of this the electricity produced by the
alternator must be rectified from A/C to D/C.
This occurs in a device called the rectifier bridge which is
made up of six diodes, 2 for every phase of alternator output. What actually
occurs during the rectification process is the alternating current that
switches from positive to negative gets cut off from going negative. These
negative waves get rerouted and become positive. This happens to all three
output phases so that the end result is a fairly direct flow of current into
the vehicle’s electrical system.
Looking at this output up close using an A/C coupled oscilloscope
you can see a bit of what is termed A/C ripple. If there is too much A/C ripple
then things like the engine control module can be damaged. The maximum amount
of ripple that the system can have before problems start is about 500 mV peak
to peak, high to low.
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Normal A/C ripple. This is harmless and normal on every car. This is the top of the A/C sign waves that come from the alternator. |
On the video that the Fuel Doctor shows on their website
they show some noise that could be compared to A/C ripple, then they plug in
their device and the noise goes away. Big deal. The noise to begin with appears
to be around 100 mV. So even if this was true A/C ripple from an alternator, or
some other such electrical noise, which it is not, the oscillation that they
say is a problem isn’t even high enough to affect anything.
These computers are digital devices. They are either on or
off, they either work or they don’t. The A/C ripple will cause them to shut
down, or it won’t. Middle ground or gray area is not something that occurs with
the function of a digital control mechanism.
Like so many of the other fuel saving devices, the Fuel
Doctor people say that you have to drive your vehicle for a while before it
will work, but they don’t really say why. Probably to blow out all of the
carbon or some such thing. The real reason that they say this is because the
device won’t work ever, but if you keep trying then I suppose you hang on to
the hope that you really didn’t waste your money, or maybe with some time you
will become bad at math and will not be able to properly calculate fuel
economy.
Ignition Enhancers
These devices usually claim that they can save you gas by
increasing the power of the spark that is responsible for igniting the air/fuel
mixture. The claims vary and the setup of these devices follow a few different
arrangements. Some of them are meant to be attached to the spark plug wires,
and some consist of special voltage enhancer that installs in series with the
coil wire. This thing is just another air gap for the spark to jump.
Those that claim to increase the voltage say that more
voltage in the secondary ignition means that the fuel will burn faster, or more
efficiently. This does not happen because the controlled burn of the air/fuel
mixture occurs once it is lit, and the voltage of the spark does not affect the
rate of combustion. The only thing that’s important is that the duration of the
spark be long enough to get a good burn. Spark duration will usually go down if
the firing voltage in the secondary goes up.
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Clip these ionizers (little rubber blocks) to your spark plug wires and you too can save save save! |
In many high performance applications increasing this voltage
is necessary because these engines have higher compression ratios which makes
ionization of the air molecules in the spark plug gap more difficult with lower
voltage. In these cases a more powerful ignition coil is used, and/or higher
voltage is used in the primary side of the ignition coil in order to produce higher
voltage in the secondary.
Increasing the secondary voltage only helps in special
applications, and really does nothing to help any situation on the average vehicle
of today, and most especially does not save you any fuel. Increasing the
secondary voltage can have a slightly negative effect in that it can cause
spark plugs to wear faster than normal. This extra voltage causes more metal
transfer between the electrodes of the plug which is how spark plugs wear out.
The other thing that can happen is that as resistance increases in secondary
ignition components, the increased voltage will make it more likely that the spark
will leave its normal path. This will cause a cylinder to misfire.
Fuel Line Magnets
These have been around for a very long time and come with
all sorts of different names printed on the package. Sometimes these devices
are referred to by their manufacturer as a fuel ionizer. This is usually the
case when they want the buyer to think that they are getting something special,
something that is not just a couple of magnets. An ionizer sounds like
something high-tech. An ion is simply an atom that is missing an electron or
has and extra electron. What does this have to do with combustion? Nothing.
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Fuel line magnets in action. |
They all work (don’t work) the same way. You attach them
around your fuel line that is going to the fuel rail where the injectors are
located. This allows the magnetic flux that emanates from the magnets to affect
the fuel as it flows to the injectors. Much of the time these fuel lines are
metal so attaching magnets to it wouldn’t even allow the field to reach the
fuel since the metal line would actually deflect the magnetic lines of flux.
The claims all vary from one magnet maker to the next. Some
claim that the hydrocarbon molecules that make up the fuel are grouped in big
clusters that when injected don’t get consumed all of the way. This leads to
inefficiency, more fuel used, less power output, and higher emissions from the
tailpipe. Some others claim that the molecules are strewn about haphazardly as
they enter the injectors which causes inefficiency in the burn. Passing through
the magnets forces the molecules to line up in nice even rows, facing the same
direction. Aligning molecules has nothing to do with combustion efficiency.
Furthermore, if aligning molecules somehow did contribute to combustion
efficiency, how would you keep the molecules aligned after they passed through
the magnetic flux? Everyone knows that molecules are always moving around
bumping into each other even when they are just sitting there.
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You can tell that they work well based on this picture. |
So the magnets are supposed to rearrange the molecules,
which then causes the fuel to burn faster, or more completely. No matter what
the claim is about the hydrocarbon molecules and how they are behaving or not behaving,
the fact of the matter is that magnets or fluxes don’t have any effect on
gasoline. Magnets only affect things that are electrical, or at least somewhat
ferrous, like iron or steel. Everyone knows what magnets stick to and what they
don’t stick to, but never the less people buy into the supposed power of
magnets and claim that they work miracles for all sorts of different things.
Hydrogen Generators
If anything has a chance to work it this, but sadly it still falls short. These devices tout the use of hydrogen (H2), or Oxyhydrogen (HHO),
as being something that can be mixed with your intake air to increase your fuel
economy. This may be true in theory and this is why many people who don’t
believe in any of the previously mentioned fuel savers will continue to come
back to these devices as being legitimate. The problem here is a matter of
scale.
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A typical HHO generator. |
Engineers have developed a number of different alternative
fuel prototypes that run on hydrogen. Most of them use hydrogen fuel cells
which use the single proton and the single electron of the hydrogen atom to produce
electricity that runs an electric motor. This is totally unlike using hydrogen
to produce combustion. Some auto companies however, have built vehicles with
normal internal combustion engines that will run on straight hydrogen instead
of gasoline. These engines work very well and produce very little pollution,
much less than an internal combustion engine because there is no carbon in any
form getting wrapped up in the combustion process.
In these engines a large volume of hydrogen is stored in a
very large and rather specialized tank onboard the vehicle. While these
vehicles work very well the problem they have is the process of sourcing the
fuel. While hydrogen is the most abundant element in the universe it does not
occur naturally anywhere on planet earth, so it is usually rendered from
splitting water molecules or breaking down hydrocarbon fuels. This process
takes a tremendous amount of electricity.
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Hydrogen fuel saver mounted under the hood. |
The hydrogen generator type fuel savers use a very small
fuel cell in which electrolysis is used to split the water molecules that are
stored in a small onboard tank. The hydrogen that results is drawn into the
intake manifold, and it does get burned with the gasoline. The total amount of
hydrogen that is used is tiny, certainly not enough to make a difference in
fuel consumption. If you were to install more fuel cells to produce more
hydrogen then you would have to have more electricity coming from the vehicle’s
alternator to produce the extra hydrogen. This would place an extra load on the
alternator and on the vehicle’s engine. If the engine is working harder, then
obviously it would be using more fuel.
Someday maybe we will have cars that run on hydrogen in some
way or another, but that day will not come until we figure out a way to produce
massive amounts of electricity in a manner that is relatively cheap and does
not pollute. Which is not to say that we couldn’t do this now.
When Will We Learn?
If you want to save fuel get a smaller car. Many people
insist on driving cars that are bigger than they need or have bigger engines
then they need. If they want to drive this kind of car then that’s fine, but
they shouldn’t expect to have 300 horsepower and 40 mpg. Other things that can
help save fuel are simple things like obeying speed limits, and avoiding jack
rabbit starts every time the light turns green. Most cars will also get better
fuel economy if speed limits are obeyed.
Vehicle maintenance also helps to save fuel. If your check
engine light is on, get it fixed because there is a good chance that the
failure will cause a reduction in fuel economy, because it most certainly causes
an increase in emissions. Remember simple things like replacing spark plugs at
recommended intervals, and keeping all services current. These things are not
difficult to remember, all you have to do is follow the manufacturers
recommended service schedule. This can always be found in the owner’s manual or
through some searching online.
What about tire pressure? Some politicians in Washington
like to tell us that we should just check our tire pressure every time the
price of gas starts to jump up. Does this really make a difference? It does make
a difference but it is pretty slight. Somewhere in the neighborhood of .03% for
every PSI that you are low. This adds up eventually but keeping your tires
inflated properly is more about making sure they don’t wear out too quickly, or
about keeping the car safe, then it is about fuel economy.
So if you want to save money at the pumps the most important
things are: drive a smaller car, drive with a little more self-control, and
take care of your car. Whatever you do, don’t buy any crazy device to hook up
to your engine, or to plug in here or there. None of these work because if they
did, everyone would have them.