ASVAB Automotive Information Practice Test 121654

Questions 5
Topics Alternator, Electric Fuel Pump, Purpose, Sensors, Springs

Study Guide

Alternator

Once the engine is running, the alternator provides electrical current to recharge the battery and power the electrical system. The alternator is driven by the engine's crankshaft and produces alternating current (AC) which is then fed through a rectifier bridge to convert it to the direct current (DC) required by the electrical system. A voltage regulator controls the output of the alternator to maintain a consistent voltage (approx. 14.5 volts) in the electrical system regardless of load.

Electric Fuel Pump

The electric fuel pump feeds pressurized fuel through a fuel filter to the fuel injectors via the fuel rail manifold. The fuel rail contains the fuel pressure regulator which ensures that the fuel injectors receive fuel at a consistent and known rate. Excess fuel bled off by the pressure regulator returns to the fuel tank through the fuel return line.

Purpose

The lubrication system lubricates engine components by putting an oil film between them to reduce friction and smooth engine operation, cools by absorbing heat from engine parts, seals the pistons and cylinders to contain combustion, cleans contaminants, and quiets engine noise.

Sensors

Sensors provide the data necessary for the vehicle's computer to make decisions and monitor everything from simple vehicle information like tire pressure to complexities like the chemical content of an engine's exhaust.

Springs

Suspension springs are made with wide gap coils of rigid steel cable and both hold the vehicle chassis up off the ground and absorb energy from wheel movement making for a smoother ride.