4 Section 1 Introduction to Automotive Technology
system. Automotive parts and systems can be orga-
nized into ten major categories:
• Body and frame—The vehicle’s body and frame
support and enclose the vehicle.
• Engine—The engine provides dependable, effi -
cient power to propel the vehicle.
• Computer systems—The computer systems
monitor and control electric/electronic circuits
to increase vehicle mechanical and electrical
effi ciency and dependability.
• Fuel system—The fuel system provides a com-
bustible air-fuel mixture to power the engine.
• Electrical system—The electrical system gen-
erates and distributes the voltage and current
needed to operate the vehicle’s electrical and
electronic components.
• Cooling and lubrication systems—Cooling and
lubrication systems prevent engine damage
and wear by regulating engine operating tem-
perature and reducing friction between inter-
nal moving parts.
• Exhaust and emission control systems—
Exhaust and emission control systems quiet
engine noise and reduce toxic substances emit-
ted during fuel evaporation and combustion.
• Drive train systems—Power is transferred from
the engine to the drive wheels by drive train
systems.
• Suspension, steering, and brake systems—
The suspension, steering, and brake systems
support and control the vehicle. They control
movement of the body and frame when the
vehicle accelerates from a standstill, cruises at
highway speeds, or slows to a stop.
• Accessory and safety systems—The accessory
and safety systems increase occupant comfort,
safety, security, and convenience.
Assembly
Part
Fuel system
Fuel
pump
Power out
Exhaust out
Ignition system
Fuel tank
Fuel in
Fuel filter
Fuel injector
Drive axle assembly
Intake manifold
Air in
Muffler
Exhaust and emission
control systems
Catalytic converter
Lubrication system
Oil pan
Exhaust
manifold
Charging
system
Cooling
system
Drive train
system
Starting system
Transmission
Engine
Throttle body
Clutch
Fuel tank
Drive shaft
Figure 1-1. An assembly is a group of parts that work together
to perform a function. For example, an engine is an assembly
that contains pistons, which convert the fuel’s heat energy into
useable kinetic energy (motion). As you will learn, an engine
has many other parts. (Audi)
Figure 1-2. Note the general location of the major vehicle systems. Study the fl ow of fuel, air, exhaust, and power.