With the price per gallon at the pump looking more
and more like the price per pound of steak, properly maintaining your vehicle is
more critical than ever. Proper maintenance will pay back dividends in the form
of increased dependability, reliability, and a more efficient engine.
Most all drivers know the words “Tune-Up”. In years
past, that meant replacing ignition points and
spark
plugs in the electrically poor ignition system, and adjusting fuel mixtures in
carburetors, and of course setting the ignition timing.
The old ignition distributors with mechanical timing
controls, and mechanical carburetors were constantly wearing, and therefore were
incapable of maintaining adjustment. Not too many years ago, tune-ups were
recommended to be performed at 12 thousand mile intervals. In fact, most new car
warranties were just 12 months and 12 thousand miles.
In today’s vehicles with electronic fuel injection,
and direct ignition systems, all of these tasks are taken care of by the on
board engine management computers. Yes Victoria, there are multiple
microprocessors on board most new vehicles. See, you may have learned something
already!
The whole concept of the electronic engine control
system is to maintain the air fuel mixture and ignition timing for longer
periods of time. This is accomplished by using electronic fuel injectors, and
computer controlled ignition timing. These computers are so powerful, they can
adjust the fuel delivery and spark timing for each individual power stroke of
your engine. They also have adaptive strategy or “Learning” abilities.
These learning abilities allow the microprocessors
to make adjustments that compensate for driver habits, and small deficiencies in
engine condition.
These feats were inconceivable with mechanical
controls. The results are obvious. More power from smaller displacement engines
that run cleaner, run better longer, and are more fuel efficient.
Reading this will
arm you with the knowledge that will help you impress your local auto technician
or mechanic.
To maintain efficiency and get the most for your
fuel dollars, today’s vehicles need a different type of “Tune-Up”. There are no
more “points and condensers”, and most new cars don’t even have distributors or
distributor caps. Today’s high energy ignition systems coupled with double
platinum tipped spark plugs are good for 100,000 miles or more. Combine this
fact with the engine control’s ability to maintain the proper air fuel ratio of
14.7 : 1, and you have longer maintenance intervals.
Keeping the air fuel ratio at 14.7 : 1 allows the
catalytic converter to better do it’s job. The converter was designed to reduce
hydrocarbon and carbon monoxide emissions as well as reducing the formation of
NOx (or oxides of Nitrogen). The design of the substrate inside the catalytic
converter includes a ceramic honeycomb coated with small traces of precious
metals including Platinum and Palladium.
These precious metal coatings get hot from the
exhaust gases, and then react with the hot exhaust gases to reduce carbon
monoxide, hydrocarbons, and Oxides of Nitrogen.
The catalytic converter is most efficient when the
air fuel mixture entering and exiting the engine’s combustion chamber is as
close to 14.7 : 1 as possible. So in reality the whole concept of electronic
engine management is to closely control the perfect or stoichiometric air fuel
ratio of 14.7 : 1.
Oxides of Nitrogen coming out of the tailpipe unite
with the atmosphere, and in the presence of sunlight add to that photo-chemical
smog that you see hanging over the major metropolitan areas. Some new systems
include EGR. EGR stands for “Exhaust Gas Recirculation”, which simply means that
a valve controls a small flow of inert or spent exhaust gases to be introduced
into the incoming air / fuel charge.
Because this inert gas won’t support combustion, the
temperature inside the combustion chamber is reduced. Reducing the combustion
chamber temperature not only extends the life of critical engine components like
valves, seal, and head gaskets, but it also helps to reduce Nox (Oxides of
Nitrogen), and is a major factor in preventing dangerous detonation or spark
knock.
Hydrocarbons are the fuel in its unburned state.
Hydrocarbons are the liquid in the tank. Hydrocarbons can be harmful as they
evaporate into our atmosphere.
Carbon Monoxide is a by-product of combustion. It is
a colorless, odorless gas that is deadly. CO is also an unstable gas. It wants
to become a good gas like its bigger brother CO2. CO2 or Carbon Dioxide is not
deadly, and is different from Co in that it has 2 molecules of oxygen. CO kills
you by robbing your blood supply and brain of oxygen molecules on its way to
becoming CO2.
The PCV system uses a vacuum controlled valve to
help to remove harmful contaminants from the engine’s crankcase as the oil gets
hot. These vapors are sort of “Vacuumed Off” so to speak and returned to the
combustion chamber to be burnt. Both of these systems aid in keeping the engine
running young, as well as reducing the formation of harmful tailpipe emissions.
The Evaporative Emission System is simply a setup
that prevents the raw fuel (Hydrocarbons) from evaporating and escaping into the
atmosphere when vehicles are parked. The system vents the fuel tank through a
series of devices including a vapor separator, a network of tubing and hoses,
and a carbon filled canister that is commonly referred to as the charcoal
filter.
All of these systems are labeled “Emission Devices”,
but they are also money saving devices. All three systems contribute to better
fuel economy, longer engine life, and engine oil that will remain cleaner for
longer drain intervals.
With PCV (Positive Crankcase Ventilation), and EGR
(Exhaust Gas Recirculation) systems, the inside of the intake manifold gets
coated with a buildup that inhibits good performance and detracts from fuel
economy. This varnish like carbon coating interferes with good airflow, and
causes a multitude of driveability problems.
A throttle body and throttle plate that is coated
with this buildup can cause stalling, hesitation, improper idle speed, and
erratic engine operation.
The fuel injector nozzles are also prone to getting
coated with chemical compounds found in the fuel itself. Things like waxy
substances and other chemicals that can prevent the injector from properly
spraying or atomizing the fuel. The injector tips are normally located just
above the intake valves and are subjected to a tremendous amount of heat. As the
engine runs, the fuel flowing through the injectors keeps them reasonably clean.
But when you shut the engine off, the injectors no longer have that cooling
effect of the fuel floe. That is when the chemicals in the gasoline begin to
form harmful deposits on the injector tips. Picture a garden hose with a steady
stream versus a finely atomized spray. Your engine needs the finely atomized
spray!
So how can you get the best mileages and performance
from your car or light truck? Follow some simple guidelines. Always buy a
quality gasoline that is labeled to contain detergent additives in it. Have your
fuel system serviced by a professional every 25 to 35 thousand miles. This
service should include cleaning the injectors, cleaning the throttle body and
plate as well as the inside of the intake manifold. Tell the technician not to
overlook the fuel filter! Change it every 25 to 35 thousand miles!
Engine oil is also critical. Be sure to use the SAE
grade and API service classifications found in your owner’s manual. Heavier oils
detract from engine power and fuel economy due to the parasitic drag created by
the heavy viscosity of the oil.
Remember,….Your vehicle was certified and tested
with the factory fill oil, so believe me on this one! Do not let anyone without
a degree in Lubrication Tribology convince you that they are smarter than the
engineers who designed the oil and engine compatibility.
You can usually change the air filter element
yourself. Unrestricted clean air is critical to performance and mileage. You
could also install a little device called “The
Tornado”. This little jewel installs easily and generates a Vortex (Swirls
the air) in your engine’s intake to better atomize the air and fuel, delivering
more power and increasing fuel mileage. Tornados are available at most all parts
stores.
In addition to maintaining the engine, be sure to
service the automatic transmission and be sure it is not slipping. Have your
mechanic check the “Lock Up” feature of your toque converter. A malfunctioning
lock up converter can cost you dearly in miles per gallon, and will generate
excess heat. Heat is the number one killer of automatic transmissions.
There is an additive called “Lubegard”,
manufactured by International Lubricants, Inc from Seattle, Washington that is
approved by Original Equipment Manufacturers to reduce operating temperatures in
automatic transmissions. I highly recommend this for your transmission. Be sure
not to accept any substitutes, as no other protectant or additive can make the
claim of OEM approval.
Maintaining tire pressures and wheel alignment as
recommended by the vehicle manufacturer will increase tire life, fuel economy,
improve safety and handling, and make driving easier. You can find the
recommended inflation pressures on the drivers door or door jamb, and in your
vehicle’s owners manual. Be sure to purchase an accurate tire pressure gauge.
Other easy things you can do yourself are to keep
the trunk as empty as possible. Many trunks in America are carrying around
hundreds of unnecessary pounds, making the engine work harder and costing you
money. Those unnecessary pounds can cause improper ride height which affects
headlight aim, and also reduces the effectiveness of the suspension systems
shock absorbers. An empty trunk will save you money on fuel as well as repairs.
Now you are armed with the facts, and the knowledge
to stop by and “talk the talk” with your favorite technician. The best auto care
advice I can give you is for you to form a relationship with a quality
automotive service facility. Get to know them, and let them get to know you.
Once there is mutual respect and trust, you are well on your way to better
automotive maintenance, and less stress.
Happy Motoring!
The more efficient an internal combustion engine
runs, the cleaner the tailpipe emissions, and the more heat energy it develops
from the fuel consumed in combustion. That kind of efficiency spells better fuel
economy, and cleaner air.
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