Automotive Systems and Engine Fundamentals

Comprehensive vocabulary flashcards covering internal combustion engine components, strokes, cooling, lubrication, exhaust, and drivetrain systems.

Chassis

The skeleton that keeps all systems and components together.

Internal Combustion Engine

A machine used by cars and other vehicles to burn fuel and air.

Common fuels

Gasoline and diesel are standard, but others include propane, natural gas, or alcohol.

Four-stroke cycle

Consists of a top dead center, or TDC, and bottom dead center, or BDC, requiring a piston to move $4$ times to complete one cycle.

Intake stroke

The phase where the intake valve opens and a vacuum sucks the air-fuel mix into the cylinder before it is sealed.

Compression stroke

Phase where the inlet valve is closed and the piston travels back up the cylinder compressing the fuel/air mixture.

Combustion stroke

Phase where the piston goes down, the explosion pushes the connecting rod, the crankshaft turns, and the flywheel keeps the engine going.

Exhaust stroke

The phase where the exhaust valve opens to push out leftover gases.

Carburetors

Mechanical devices that mix fuel and air together.

Fuel injectors

Components that dispense fuel directly into the engine’s air stream.

Throttle

A valve used to regulates engine speed.

Pistons

Cylindrical objects with a solid crown at the top that move up and down in each cylinder.

Piston rings

Seals between the piston and cylinder that prevent gases from leaking out.

Cylinders

The site of the piston and air-fuel mixture where energy is produced.

Cylinder head

The part of the cylinder above the piston housing the combustion chamber, valves, and ports.

Combustion chamber

Area located inside the cylinder head, directly above the piston.

Intake valves

Components that allow the air-fuel mix to enter the combustion chamber.

Exhaust valves

Components that allow waste gases to exit the combustion chamber after combustion.

Crankshaft

Part that converts a piston’s up-and-down motion into a rotary motion.

Camshaft

Component that opens and closes intake and exhaust valves, and usually controls the oil pump.

Wrist pins

Parts that connect the piston to the connecting rod.

Connecting rods

Parts that connect each piston and wrist pin assembly to the crankshaft.

Starter

The motor used to begin engine operation.

Alternator

Sends electric current to the battery to keep it charged and powers electronics while the engine is running.

Cooling systems

Systems designed to prevent an engine meltdown.

Lubrication systems

Systems that keep the engine moving smoothly.

Oil pump

Component that pushes motor oil through the engine.

Oil galleries

Specific pathways that oil takes through the engine.

Oil pan

Site at the bottom of the engine where all the oil pools.

Pickup tube and screen

Mechanism where a tube sends oil to the pump and a screen filters out solid materials.

Oil filter

Cleans out contaminants before oil is circulated back through the engine.

Exhaust manifold

Connects to the exhaust ports on the cylinder head where combustion occurs.

Catalytic converter

Passageways with catalysts that transform toxic compounds into less-harmful compounds like carbon dioxide and water.

Muffler

A place within the exhaust system for gases to expand quietly.

Tailpipe

The exit door for exhaust gases.

Emissions-control systems

Systems responsible for filtering out pollutants.

Positive-crankcase ventilation

A method forcing unspent or partially spent fuel back into the cylinder to be burned.

Air-injection system

Forces air into the exhaust system to reuse unburned fuel before it exits the tailpipe.

Exhaust-gas-recirculation system

Controls nitrogen-oxide emissions by forcing some gases back into the cylinders.

Rear-wheel drive

System where rear wheels push the car via a drive shaft extending from the transmission to the rear axle.

Front-wheel drive

System where front wheels pull the car via a drive shaft extending from the transmission to the front axle.

All-wheel drive (four-wheel drive)

System where all wheels push and pull the car simultaneously.

Transmission

Changes engine speed in relation to the speed of the rear wheels.

Struts

Components that support vehicle weight and prevent it from collapsing to the ground.

Shock absorbers

Part of the struts consisting of a piston inside a hydraulic fluid-filled, sealed tube.

Tires

The vehicle’s first contact with the road; air inside provides stability and handling.

Springs

Components that hold the chassis up and allow wheels to move up and down smoothly.

Steering knuckle

The connection point between a tie rod and a wheel that controls turning.

Control arms (A-arms)

Metal pieces connecting the steering knuckle with ball joints to keep it vertical during wheel movement.

Tie rods

Parts that transfer force from the steering linkage or rack to the steering knuckle to turn the wheel.

Drum brakes

System where hydraulic cylinders force two brake shoes against a rotating metal drum.

Disc brakes

System where a master cylinder forces a caliper and brake pads to squeeze against a rotor disc.