Question 1

Air Fuel Ratio Sensor

Accepted Answer

A device that provides a more precise reading of the air-fuel mixture in an engine's exhaust than a traditional oxygen sensor.

Question 2

Knock Sensor

Accepted Answer

A sensor that detects engine knock or pinging, which can indicate a misfire or poor fuel/air mixture.

Question 3

Variable Valve Timing (VVT)

Accepted Answer

A system that allows the valve timing to be adjusted on the fly, improving engine performance.

Question 4

Fuel Trim

Accepted Answer

A term used to describe how much the fuel delivery system is adjusted to maintain the correct air/fuel mixture.

Question 5

OBD-II

Accepted Answer

On-Board Diagnostics II, a system in modern vehicles that monitors and reports on various vehicle performance parameters.

Question 6

Mass Airflow Sensor (MAF)

Accepted Answer

A device used to measure the mass flow rate of air entering the engine.

Question 7

Throttle Position Sensor (TPS)

Accepted Answer

A sensor that measures the position of the throttle in an internal combustion engine.

Question 8

Crankshaft Position Sensor

Accepted Answer

A sensor that monitors the speed and position of the crankshaft, which can influence fuel injection and ignition timing.

Question 9

Closed Loop Operation

Accepted Answer

A state where the vehicle's computer system uses the O2 sensor to check its own work and adjust fuel mixture accordingly.

Question 10

Evaporative Emission Control System (EVAP)

Accepted Answer

A system designed to prevent gasoline vapors from escaping into the atmosphere from a vehicle's fuel system.

Question 11

Long-Term Fuel Trim (LTFT)

Accepted Answer

A fuel trim used for continuous minor adjustments to the fuel delivery system based on feedback from the oxygen sensors.

Question 12

Short-Term Fuel Trim (STFT)

Accepted Answer

A fuel trim used for immediate changes in the air/fuel mixture based on sensor readings.

Question 13

EGR Valve

Accepted Answer

Exhaust Gas Recirculation Valve, a device that reintroduces exhaust gases into the engine to lower combustion temperatures and reduce NOx emissions.

Question 14

Positive Crankcase Ventilation (PCV) Valve

Accepted Answer

A device that helps remove harmful vapors from the engine.

Question 15

Camshaft Position Sensor

Accepted Answer

A sensor that monitors the rotational position of the camshaft, which influences fuel injection and valve timing.

Question 16

Intake Air Temperature Sensor

Accepted Answer

A sensor that measures the temperature of the air entering the engine.

Question 17

Coolant Temperature Sensor

Accepted Answer

A sensor that measures the temperature of the engine coolant.

Question 18

Engine Control Module (ECM)

Accepted Answer

The 'brain' of the engine control system, controlling many aspects of engine performance.

Question 19

Ignition Control Module (ICM)

Accepted Answer

The component that controls the ignition system, including the spark and timing.

Question 20

Fuel Pressure Regulator

Accepted Answer

A device that maintains the correct fuel pressure in the fuel system.

Question 21

Fuel Injector

Accepted Answer

A device that sprays fuel into the engine in a precise pattern for optimal combustion.

Question 22

Throttle Body

Accepted Answer

The part of the air intake system that controls the amount of air flowing into the engine.

Question 23

Catalytic Converter

Accepted Answer

A device that reduces harmful emissions from the engine's exhaust gases.

Question 24

Oxygen Sensor

Accepted Answer

A sensor that monitors the level of oxygen in the engine's exhaust gases.

Question 25

Wideband Oxygen Sensor

Accepted Answer

An oxygen sensor that provides a broader and more accurate reading of oxygen levels in the exhaust.

Question 26

Fuel Pump

Accepted Answer

A device that moves fuel from the tank to the engine.

Question 27

Ignition Coil

Accepted Answer

A device that transforms the battery's low voltage to the thousands of volts needed to create an electric spark in the spark plugs.

Question 28

Spark Plug

Accepted Answer

A device that ignites the air/fuel mixture in the engine cylinders.

Question 29

Distributor

Accepted Answer

A device that directs high-voltage from the ignition coil to the spark plugs in the correct firing order.

Question 30

Direct Fuel Injection

Accepted Answer

A type of fuel injection where fuel is injected directly into the combustion chamber.

Question 31

Sequential Fuel Injection

Accepted Answer

A type of fuel injection where fuel is injected into each cylinder in sequence, closely matching the firing order.

Question 32

Engine Misfire

Accepted Answer

A condition where an engine does not fire on all cylinders, leading to a loss of power and potential damage.

Question 33

Variable Intake System

Accepted Answer

A system that alters the intake path length for better engine performance.

Question 34

Turbocharger

Accepted Answer

A device that uses exhaust gases to spin a turbine and compress incoming air, increasing horsepower.

Question 35

Supercharger

Accepted Answer

A device that compresses the air entering the engine to increase horsepower; driven by the engine rather than exhaust gases.

Question 36

Idle Air Control Valve

Accepted Answer

A component that allows bypass air to control idle speed when the throttle is closed.

Question 37

Manifold Absolute Pressure Sensor (MAP)

Accepted Answer

A sensor that provides information about the difference between atmospheric pressure and the pressure in the intake manifold.

Question 38

Canister Purge Valve

Accepted Answer

A part of the EVAP system, it controls the release of fuel vapors from the charcoal canister to the engine.

Question 39

Fuel Rail

Accepted Answer

The main fuel delivery assembly in an engine, which supplies fuel to the injectors.

Question 40

Heated Oxygen Sensor (HO2S)

Accepted Answer

An oxygen sensor with a built-in heater to bring it up to operating temperature more quickly.

Question 41

Ignition Timing

Accepted Answer

The timing of when a spark will occur in the combustion process, which is critical for engine performance.

Question 42

Emissions Control Systems

Accepted Answer

Systems designed to reduce the amount of pollutants produced by an engine.

Question 43

Engine Compression Ratio

Accepted Answer

The ratio of the cylinder's volume at BDC to its volume at TDC; higher ratios can lead to increased power output, but may also increase engine knock.

Question 44

Variable Displacement

Accepted Answer

An engine technology that deactivates certain cylinders under light load conditions to improve fuel economy.

ASE A8 - Engine Performance Advanced Terms Flashcards