Water Pump The water pump is a vital component of the automotive cooling system, responsible for maintaining a continuous flow of coolant between the engine block and the radiator. Its operation ensures efficient dissipation of the heat generated during internal combustion. Typically driven by the timing belt or auxiliary belt, it includes a centrifugal impeller and a shaft connected to bearings that allow rotational motion. Pump failure can lead to overheating, coolant loss, and structural damage to the engine. Its periodic inspection includes checking for leaks, abnormal noises, and turning tolerances.

Car Filters Vehicle filters are essential components that protect the engine and other systems from external contaminants. The air filter prevents particles such as dust and pollen from entering the combustion chamber. The oil filter retains impurities from the lubricant, ensuring the protection of internal parts. The fuel filter ensures that the fuel reaches the injection system clean. The cabin filter improves interior air quality, while particulate filters in diesel engines reduce harmful emissions. Regular maintenance and the use of appropriate filters extend the vehicle's lifespan and prevent breakdowns. Periodic inspection is part of the basic routines recommended by manufacturers.

Brake Pads Brake pads are the key element of the braking system. When the pedal is pressed, hydraulic fluid activates the caliper pistons, which press the pads against the disc, generating friction and converting kinetic energy into heat. This contact stops the wheels from rotating and reduces the vehicle's speed. The friction material, composed of resins, fibers, and metallic or ceramic particles, is designed to withstand high temperatures and controlled wear. As it wears, its thickness and braking capacity decrease, so it must be inspected and replaced periodically.

Brake Discs Brake discs are part of the friction braking system and rotate attached to the wheel hub. When the pedal is pressed, the hydraulic pump sends pressure through the brake fluid to the caliper pistons, which press the brake pads against the disc surface. This friction converts kinetic energy into heat, slowing the wheel and stopping the vehicle. Discs are usually ventilated or solid; their slotted or perforated design facilitates heat dissipation and prevents the buildup of gases and debris.

Shock Absorbers A car shock absorber is a hydraulic device that controls suspension oscillations and keeps the wheels in contact with the road. It consists of an oil-filled cylinder and a piston attached to a rod. When the wheel hits a bump, the piston moves within the cylinder, forcing the oil to pass through calibrated valves. This restriction generates a damping force proportional to the speed of the movement, dissipating kinetic energy into heat. During rebound, the fluid passes through the return valve, balancing the movement. This prevents swaying, improving stability and comfort.

Air suspensions are advanced systems that replace traditional metal springs with pressurized air bellows. These bellows, powered by an electric compressor, allow the vehicle's height and stiffness to be adjusted in real time. The system includes level sensors, control valves, and an electronic unit that regulates pressure according to load and terrain conditions. Its main advantage is the ability to maintain a constant height, improve ride comfort, and optimize dynamic stability. They are particularly used in high-end vehicles, off-road vehicles, and models focused on adaptive driving. Although they offer significant benefits in comfort and performance, their technical complexity entails higher maintenance costs and potential breakdowns due to leaks or compressor failure.

Clutches The clutch connects and disconnects the engine from the gearbox through controlled friction between the clutch discs and the flywheel. It consists of the clutch disc, the pressure plate, the spring (or diaphragm), and the clutch release bearing. When the pedal is pressed, the release bearing pushes the diaphragm, releasing pressure on the clutch disc and separating the disc from the flywheel, interrupting torque transmission. When the clutch is released, the spring presses the clutch disc against the disc and flywheel again, restoring engagement. This mechanism smooths gear shifts and protects transmission components, ensuring efficiency.

Radiator The radiator is part of the cooling system and dissipates the heat generated by the engine. Coolant circulates from the pump to the engine block, absorbing heat. Upon entering the radiator, the hot fluid passes through metal tubes and fins exposed to airflow or the fan. This air removes heat from the coolant and reduces its temperature. The cooled coolant returns to the engine in a cycle. The pressure cap keeps the system airtight and raises the boiling point. A thermostat regulates the flow to the radiator based on temperature. A fan preferably reinforces circulation.

Starter Motor The starter motor transforms the battery's electrical energy into mechanical motion to start the engine. Turning the key activates the 12 V electric solenoid, which engages the drive pinion and closes the current circuit to the rotor. As it rotates, the rotor generates the torque needed to rotate the crankshaft until combustion begins. A freewheel or bendix disengages the pinion from the flywheel when the engine reaches operating speed. Return springs and brushes ensure a permanent seal and a quick start response.

Alternator The alternator converts the engine's mechanical energy into electrical energy to charge the battery and power vehicle systems. A belt attached to the crankshaft turns the rotor, which generates a magnetic field around the stator. This induces alternating current in the stationary winding. A diode bridge rectifier transforms the alternating current into direct current.

Air Conditioning Compressor A car's air conditioning compressor acts as the air conditioning system's pump, compressing the refrigerant gas to high pressure. Driven by the engine via a belt and an electromagnetic clutch, its piston or rotor raises the pressure and temperature of the refrigerant. The compressed gas is directed to the condenser, where it releases heat and liquefies. An expansion device then reduces the pressure, cooling the liquid before it reaches the evaporator, where it absorbs heat from the passenger compartment. A pressure regulator ensures stability throughout the cycle, and periodic oil maintenance prolongs its useful life.

Spark Plugs The spark plug is the key component of the ignition system in gasoline engines. Its threaded end inserts into the cylinder head and generates the spark that ignites the air-fuel mixture at the precise moment. Its precision, materials, and design directly influence engine power, efficiency, and emissions. The spark plug transforms electrical energy into a high-voltage arc: A coil or transformer raises the voltage to tens of thousands of volts. This voltage travels through the high-voltage cable to the spark plug terminal. When the potential difference exceeds the dielectric strength of the gas, an electric arc forms. The arc ionizes the gases, allowing the current to flow and generating the spark that ignites the mixture.

Glow Plugs A diesel car glow plug, also known as a preheating plug, raises the temperature of the combustion chamber before a cold start. Its purpose is to facilitate diesel combustion in low-temperature conditions, improving engine performance and reducing polluting emissions. When the ignition is turned on, the control unit sends electrical current to each glow plug. The glow plug's internal resistance quickly heats up to over 800°C, transferring heat to the compressed air in the cylinder. Once the optimal temperature is reached, the system cuts off the power supply and the engine proceeds to inject fuel.

Ignition Coils The ignition coil is a high-voltage transformer whose purpose is to raise the 12 V of the battery to tens of thousands of volts. This electrical impulse is essential to generate the spark in the spark plug and ensure the ignition of the air-fuel mixture. The coil works under the principle of electromagnetic induction. When current flows through the primary winding, it creates a magnetic field around an iron core. When this current is abruptly interrupted, the variation in the field induces a high voltage in the secondary winding.

Lambda Probes The lambda probe, also known as an oxygen sensor, measures the oxygen concentration escaping from the engine's exhaust in real time. Based on its readings, the ECU adjusts the air-fuel mixture to optimize power, reduce fuel consumption, and minimize harmful emissions. When it reaches its operating temperature (300–600°C), the probe's ceramic generates a voltage proportional to the difference in oxygen between the exhaust gases and the outside air. A high voltage indicates a low oxygen content (rich mixture); a low voltage indicates excess oxygen (lean mixture). The ECU activates the internal resistor to bring the probe up to temperature. Once heated, the ceramic produces a voltage between 0.1 V and 0.9 V depending on the air-fuel ratio. The ECU interprets this signal and modifies the injector opening timing. The cycle is repeated hundreds of times per second, keeping the mixture around the stoichiometric ratio (λ = 1).

EGR Valves The EGR (Exhaust Gas Recirculation) valve regulates the recirculation of exhaust gases into the intake manifold. When the ECU detects conditions of a warm engine with low load and moderate rpm, it sends a signal to the actuator (electric or pneumatic) that opens the valve. The recirculated gases mix with fresh air, reducing combustion temperatures and the formation of nitrogen oxides (NOx). When maximum power is required, the valve closes, diverting all exhaust gas to the exhaust system. A return duct manages excess gases and contributes to internal engine cooling.

Turbochargers: A turbocharger harnesses the kinetic energy of exhaust gases to increase the density of air entering the cylinders. When the engine expels gases at high speed, they are channeled into the turbine, which spins a common shaft connected to the compressor. The compressor draws in air from outside, compresses it, and sends it under pressure to the intake manifold. Thanks to the turbocharger, greater power and torque are achieved without increasing displacement, improving efficiency and reducing emissions.

Injection Pumps Injection pumps are essential components in diesel engines, responsible for generating and distributing the pressure necessary to atomize the fuel into the combustion chamber. Their precision and reliability directly determine engine performance, efficiency, and emissions. Injection pumps transform the mechanical energy of the crankshaft into hydraulic pressure. The pump shaft drives pistons or rotating elements. The fuel is compressed to pressures of hundreds or thousands of bars. The pressure is released in a controlled manner to the injectors, synchronized with the engine cycle. Proper fuel atomization depends not only on pressure, but also on the exact timing of the injectors' opening.

Injectors The diesel injector meters and atomizes the fuel into the combustion chamber. It receives high-pressure diesel fuel generated by the injection pump, which pushes the fuel toward a spring-sealed needle valve. When the pressure exceeds the threshold, the needle rises, allowing the fuel to pass through the nozzle orifices in the form of fine droplets. This atomization optimizes the air-fuel mixture, promoting more complete and efficient combustion. When the pressure is released, the spring closes the valve, stopping the flow. The process is repeated with each cycle to ensure optimal power and economy.