ASVAB Automotive Information Practice Test 627970 Results

Your Results Global Average
Questions 5 5
Correct 0 3.50
Score 0% 70%

Review

1

What does the timing belt do?

64% Answer Correctly

synchronizes the cam and the camshaft

synchronizes the camshaft and the crankshaft

calibrates the speedometer

synchronizes each piston to the crankshaft


Solution

Maintaining proper synchronization between the rotation of the camshaft and the rotation of the crankshaft is critical to ensure that the engine's valves open and close at the proper times during each cylinder's intake and exhaust strokes.


2

The fuel injector is regulated by the __________ which is the main computer that controls engine and transmission functions.

60% Answer Correctly

vehicle control module

transmission control module

powertrain control module

computer control module


Solution

The fuel injector sprays fuel into the air stream that's being fed into the cylinder head via the intake valve. The timing and amount of fuel are regulated by the powertrain control module (PCM) which is the main computer that controls engine and transmission functions.


3

The stoichiometric ratio is approximately:

70% Answer Correctly

1:14.7

1:1

14.7

14.7:1


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.


4

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

73% Answer Correctly

wheel hub

strut

wheel cylinder

knuckle


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


5

When a car engine is running, what provides electrical current to recharge the battery and power the electrical system?

84% Answer Correctly

camshaft

alternator

battery

solenoid


Solution

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.