Chapter 9 | 535acceleration. Using cruise control on highway trips can help maintain a con-
stant speed and reduce fuel consumption. Steady driving is also safer, easier
on the nerves, and better for the heart.
Anticipate Traffic Ahead and Avoid Tailgating
A driver can reduce fuel consumption by up to 10 percent by anticipating
traffic conditions ahead and adjusting the speed accordingly, and avoiding
tailgating and thus unnecessary braking and acceleration (Fig. 9–63). Accel-
erations and decelerations waste fuel. Braking and abrupt stops can be mini-
mized, for example, by not following too closely, and slowing down gradually
by releasing the gas pedal when approaching a red light, a stop sign, or slow
traffic. This relaxed driving style is safer, saves fuel and money, reduces pol-
lution, reduces wear on the tires and brakes, and is appreciated by other driv-
ers. Allowing sufficient time to reach the destination makes it easier to resist
the urge to tailgate.
Avoid Sudden Acceleration and Sudden Braking
(Except in Emergencies)
Accelerate gradually and smoothly when passing other vehicles or merging
with faster traffic. Pumping or hard pressing the accelerator pedal while driv-
ing causes the engine to switch to a “fuel enrichment mode” of operation
that wastes fuel. In city driving, nearly half of the engine power is used for
acceleration. When accelerating with stick-shifts, the RPM of the engine
should be kept to a minimum. Braking wastes the mechanical energy pro-
duced by the engine and wears the brake pads.
Avoid Resting Feet on the Clutch or Brake Pedal while Driving
Resting the left foot on the brake pedal increases the temperature of the brake
components, and thus reduces their effectiveness and service life while wasting
fuel. Similarly, resting the left foot on the clutch pedal lessens the pressure on
the clutch pads, causing them to slip and wear prematurely, wasting fuel.
Use Highest Gear (Overdrive) During Highway Driving
Overdrive improves fuel economy during highway driving by decreasing the
vehicle’s engine speed (or RPM). The lower engine speed reduces fuel con-
sumption per unit time as well as engine wear. Therefore, overdrive (the fifth
gear in cars with overdrive manual transmission) should be used as soon as
the vehicle’s speed is high enough.
Turn the Engine Off Rather Than Letting It Idle
Unnecessary idling during lengthy waits (such as waiting for someone or for
service at a drive-up window, being stuck in traffic, etc.) wastes fuel, pollutes
the air, and causes engine wear (more wear than driving) (Fig. 9–64). There-
fore, the engine should be turned off rather than letting it idle. Idling for
more than a minute consumes much more fuel than restarting the engine.
Fuel consumption in the lines of drive-up windows and the pollution emitted
can be avoided altogether by simply parking the car and going inside.
FIGURE 9–63
Fuel consumption can be decreased by
up to 10 percent by anticipating traffic
conditions ahead and adjusting
accordingly.
© Vol. 23/PhotoDiscFIGURE 9–64
Unnecessary idling during lengthy
waits wastes fuel, costs money, and
pollutes the air.