Sunday, September 8, 2013


1. Shift to Neutral When Stopped.
Notice that shifting your automatic or manual
transmission into neutral calms down your
engine note and drops the rpm. That saves
gas. Shift into neutral even for a long traffic
2. Don't Rev the Engine Before Shutting Off the
Many of us learned to do this on carburetor-
equipped engines in the belief that stomping
the gas pedal as we turned off the switch would
"prime" the carb (put a jolt of gasoline in its
bowl). Most of the time, it did little or no good
even for a carbureted engine.
For today's fuel-injected engines, it's a
complete waste of fuel. Not only that, but the
final spurt of gasoline also winds up dumped
on the cylinder walls where it can wash away
the essential lubricant, paving the way for
increased wear.
3. Don't Race the Engine at Stoplights
4. Ease Up on the Accelerator
Fuel consumption is directly related to how
hard the engine is working. Ask it to race away
from a stop rather than accelerate sensibly, and
you'll be visiting the gas station all too
frequently. Guaranteed. Ask it to barge up a
steep grade rather than feathering the throttle
just enough to sustain momentum, and you'll
watch the needle on your gas gauge move too
quickly toward "E."
Even jabbing the accelerator during passing
maneuvers or lane changes eats away at fuel
economy. On the highway, zooming up to the
traffic ahead, then having to hit your brakes, is
a fuel-wasting exercise and a sure sign of an
impatient driver. The best drivers are smooth
and efficient in every move they make.
5. Lose Traction, Lose Fuel
Even if you're not trying to race away from a
stop, you may find your tires slipping,
especially on wet or gravel surfaces. Each time
a tire slips, whatever the cause, you're losing
gas mileage as well as endangering yourself.
Take care when starting off on slippery or
unpaved roads. Slow down on rough

6. Consider RPM and MPG
An engine's workload is determined by how
fast the crankshaft is turning. The crankshaft
transmits engine power to the transmission
and then to the wheels, and crankshaft speed
is measured in revolutions per minute, as
indicated on a tachometer.
A manual transmission gives the driver full
control over rpm because the driver can make
the engine speed up or slow down via gear
selection. The lower the gear, the higher the
rpm. The higher the rpm, the more torque the
engine is producing, and the more fuel it is
using. Automatic transmissions take some of
this control out of the driver's hands, but they,
too, can be manipulated to maximize fuel
7. Shift Smartly
With a manual gearbox, shift into the upper
gears quickly. Optimal shift points vary,
depending on the engine/gearing combination,
but for best economy you might need to shift to
second by about 15 mph, and reach top gear
by the time you're traveling 30 to 35 mph.
Rule of thumb: If the engine is revving faster
than necessary to sustain an even road speed,
move to the next higher gear. Downshifting
follows a similar standard. If the gas pedal has
to stay close to the floor to maintain speed, you
probably belong in the next lower gear.
"Lugging" in too high a gear isn't good for the
engine or your finances.
8. Watch the Tachometer
Because tachometers are no longer limited to
performance models, more drivers than ever
have a chance to pay attention to engine speed
as well as road speed. This allows you to find
the engine's most efficient rpm and stay close
to that point whenever feasible. What speed is
The exact figure depends on the engine but is
typically the speed at which it produces the
greatest torque output. For economy's sake,
it's generally wise to remain below 3,000 rpm
most of the time and to shift into the next gear
before the engine gets much beyond its
optimum rpm level. Too low an engine speed
does nothing for your finances, so running
below 1,500 isn't ordinarily a good idea.
9. Get the Most from Your Automatic
An automatic transmission liberates you from
shifting gears yourself, but nothing is free, and
an engine must work a little harder and use a
bit more gas to transmit power through an
automatic transmission than a manual. For
proof, look no further than EPA fuel economy
estimates, which are invariably lower for an
automatic transmission than for that same
vehicle equipped with a manual transmission.
Still, there are some things you can do to
maximize fuel efficiency in an automatic-
transmission vehicle.
During acceleration, listen as the engine note
rises and then falls to get a sense of when the
transmission is reaching the "top" of one gear
ratio and changing down to the next lower
ratio. Also, watch the needle on the tachometer
climb up the rpm range and descend
correspondingly. Remember, the higher the rpm,
the more fuel you're burning.
Some automatic transmissions tend to stay in
lower gears a little too long for peak economy.
You can sometimes coax the transmission into
shifting to high gear earlier than usual by
letting up on the gas as you pass 30 mph or
so. Then, once it's in top gear, continue to
accelerate very gradually.
10. Watch That Little OD Light
Virtually all manual and automatic
transmissions have an overdrive gear that can
be employed to save fuel. It's usually the
highest-numbered gear (or gears), and it lets
the engine run at a slower speed (or lower rpm)
while the car maintains the same road speed.
If you're looking to save gas, get into an
overdrive gear as soon as possible and stay
there until you need the extra power afforded
by a lower gear.
With an automatic transmission, a lot of that
decision making is out of your hands.
Automatics tend to move to the highest gear on
their own, precisely to save fuel; at cruising
speeds, overdrive (OD) kicks in. But you can
shift into and out of OD. On newer cars, it's
usually done via a button on the shift lever.
Typically, an "OD" light illuminates in the
instrument panel when an automatic is shifted
out of OD. If you have inadvertently shifted out
of OD, press the button to get back in for
optimal fuel economy.
Many modern automatic transmissions allow
drivers to change gears manually by moving
the shift lever through a separate gate. This
doesn't duplicate the degree of gear control
afforded by a manual transmission, but it will
allow you to select a lower gear for more
throttle response. Doing so increases engine
rpm and burns more gas. For best fuel
efficiency, shift into the highest gear whenever
possible or simply shift into Drive and let the
automatic do what it's designed to: Select the
most economical gear at each step of the way.
11. Make Sure Nothing's Afoot
Don't drive with a foot resting on the brake
pedal, however lightly. Even the slightest
application of the brakes while moving will drag
down fuel economy. It'll place an unnecessary
burden on the engine and transmission. You'll
wear out your brakes rapidly, as well.
Even when your car isn't moving, you should be
thinking about ways to save gas. In our final
section, we'll take a look at some ways to
conserve fuel while your car is standing still.
12. Practice Mind Over MPG
We tend to allow our emotions to affect our
driving. Whether you are elated or angry, calm
down before getting behind the wheel.
Emotionally intense drivers are a lot more likely
to engage in fuel-wasting (and dangerous)
acts: gunning the engine, spinning the wheels,
and worse
13. Fill the Tank Only When Needed
No point stopping for gas when there's still
plenty in the tank. Let it get down to about
one-quarter full. Extra stops waste time, and
keeping more fuel than needed in the tank adds
unwanted weight to your vehicle. A gallon of
gas weighs roughly 6 pounds, and the more
weight you haul around, the more fuel you'll
Note that there are important exceptions to this
rule. During extremely cold weather, keeping
the tank near full minimizes the amount of
condensation, or water, that can form in the
tank. Excess condensation can promote fuel-
line freeze and other problems.
Additional exceptions depend on your personal
travel patterns. If you regularly drive long
distances, at odd hours, in desolate conditions,
or in hazardous weather, it's in your interest to
keep a generous supply of gas in the tank. Plan
for the unexpected.
14. Buy Gas on Cool Mornings
Liquids expand when warm, and that includes
gasoline. So you actually get a bit more for the
same amount of cash by buying gas when it's
most dense, even though the pump shows the
same total.
15. Change the Air Filter
Some experts say not to expect a huge mileage
boost from keeping your engine's air filter fresh;
others say a clogged air filter can reduce gas
mileage by as much as 10 percent.
In any case, changing an air filter is a simple
task you can perform, and a properly operating
air filter is essential for keeping the engine
clean inside. A clogged or really dirty air filter
cuts off air to the engine, and there's no doubt
that hurts performance and fuel economy.
Maintain the Cooling System
An engine that runs too cool or too hot may
waste 10 to 15 percent of the fuel you put into
your gas tank. Your engine's operating
temperature is governed primarily by the
coolant fluid and the engine's thermostat.
Coolant is a blend of antifreeze and water that
helps maintain proper engine temperature in
both hot and cold weather conditions. The
proper coolant blend is usually a 50-50 mix of
antifreeze and water. The level should be
maintained as indicated on the underhood
reservoir, and the coolant should look clean.
A malfunctioning thermostat might stick open,
which lengthens engine warm-up time and
lowers the operating temperature, both of which
hamper gas mileage. It could also stick in the
closed position, which can cause the engine to
overheat. Watch your dashboard coolant
temperature gauge as a guide. Even if your car
has no gauge but a warning light, one way to
discover a malfunctioning thermostat is to pay
attention to your car's heater. If it isn't
delivering warm air within five minutes, even in
freezing weather, get that thermostat checked.
16. Check Belt Tensions
Belts that drive the air conditioner, water pump,
and power-steering pump must be tight
enough not to slip, but not so tight as to bind.
A rule of thumb used to suggest that belts
needed a half-inch of slack, but some of
today's engines are more delicate. Their belts
must be checked by following the manual's
instructions exactly, possibly using a
measuring instrument to get tension exactly
right. In any case, don't forget to shut off the
engine before putting your hand anywhere near
a belt.
17. Pay Attention to the Brakes
Take note of suspicious symptoms. A dragging
brake is not only dangerous but can also drag
gas mileage down with every rotation. Brake
maintenance is best left to an experienced
mechanic. However, if you feel comfortable
putting a corner of your car on a jack, as
though you're changing a tire, give the wheel a
spin to see if anything seems to be dragging. If
it is, contact your mechanic. And make sure the
parking brake is never left engaged when you
start the car.
18. Maintain Wheel Alignment and Tire Balance
Professional equipment is needed to check
these, but a misaligned front end or unbalanced
tire can rob plenty of mileage. Is the car pulling
to the side? Chances are a realignment is
needed. Unless front wheels are pointing ahead
properly, the tires might scrub against the
pavement and steal fuel by straining the
engine. Vibration at various road speeds
suggests the need for balancing. An
unbalanced tire also soaks up excess gas.


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