ASVAB Automotive Information Practice Test 454838 Results

Your Results Global Average
Questions 5 5
Correct 0 2.95
Score 0% 59%

Review

1

What is the function of the alternator?

59% Answer Correctly

replaces the electrical energy that the car draws from the battery

converts motion from the wheels into DC power

charges the battery when the car is not running

provides AC power for the car's electrical components


Solution

An automobile's electrical system runs on DC power and the bulk of that power is supplied by the battery. The alternator converts the motion of the rotor into AC power which is then fed through the rectifier to convert it to DC power that both the car and the battery can use.


2

The fuel pressure regulator ensures that the fuel injectors receive fuel at a consistent and known rate. The fuel pressure regulator is part of the:

40% Answer Correctly

electric fuel pump

fuel rail

fuel filter

fuel manifold


Solution

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.


3

What combines the suspension spring and shock absorber into one unit?

73% Answer Correctly

wheel hub

wheel cylinder

knuckle

strut


Solution

Because a compressed spring will ex­tend violently, shock absorbers must be used to dampen the spring’s compression and extension cycles. Struts combine the spring and shock into one unit


4

The piston moves downward in the cylinder creating a vacuum that pulls an air-fuel mix into the combustion chamber. This describes which engine stroke?

68% Answer Correctly

power

intake

compression

exhaust


Solution

The four-stroke piston cycle of internal combustion engines starts with the piston at top of the cylinder head (top dead center or TDC) during the intake stroke. The piston moves downward in the cylinder creating a vacuum that pulls an air-fuel mix into the combustion chamber through the now open intake valve.


5

Too much air results in a __________ air-fuel mixture that burns more slowly and hotter.

57% Answer Correctly

heavy

light

rich

lean


Solution

The stoichiometric ratio defines the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air. For gasoline fuel, the stoichiometric ratio is about 14.7:1 or for every one gram of fuel, 14.7 grams of air are required. Too much air results in a lean air-fuel mixture that burns more slowly and hotter while too much fuel results in a rich mixture that burns quicker and cooler.