Auto and Shop Information: Automotive Systems Flashcards
6 cards from real AFCT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Auto and Shop Information: Automotive Systems flashcards as text
What is the function of the oxygen sensor (O2 sensor) in a modern vehicle?
Answer: To monitor oxygen levels in the exhaust to help the engine computer adjust the air-fuel ratio
The O2 sensor measures the amount of oxygen in the exhaust gases. The engine control module (ECM) uses this data to adjust fuel injection for optimal combustion, improving fuel efficiency and reducing emissions.
What is the role of the differential in a rear-wheel-drive vehicle?
Answer: To allow the rear wheels to rotate at different speeds during turns
The differential allows the outer wheel to rotate faster than the inner wheel during turns. Without it, the driven wheels would be forced to spin at the same speed, causing tire scrubbing and handling problems.
What happens when a vehicle's serpentine belt breaks while driving?
Answer: Multiple systems fail including the alternator, power steering pump, water pump, and AC compressor
The serpentine belt drives multiple engine accessories simultaneously. When it breaks, the alternator stops charging, the power steering pump loses pressure, the water pump may stop circulating coolant, and the AC compressor ceases operation.
What is the purpose of the mass airflow (MAF) sensor in a fuel-injected engine?
Answer: To measure the volume and density of air entering the engine
The MAF sensor measures the amount and density of air entering the engine. The engine control module uses this information to calculate the correct amount of fuel to inject for optimal combustion.
What type of suspension system uses a single assembly containing the spring and shock absorber together?
Answer: MacPherson strut
The MacPherson strut combines the shock absorber and coil spring into a single compact unit. It serves as both the suspension damping element and a structural component of the steering knuckle assembly.
What is the function of the EGR (Exhaust Gas Recirculation) valve?
Answer: To recirculate a portion of exhaust gases back into the intake manifold to reduce nitrogen oxide emissions
The EGR valve routes a controlled amount of exhaust gas back into the combustion chambers. This dilutes the air-fuel mixture and lowers combustion temperatures, significantly reducing the formation of harmful nitrogen oxides (NOx).