ASVAB Automotive Information Practice Test 354986 Results

Your Results Global Average
Questions 5 5
Correct 0 3.02
Score 0% 60%

Review

1

Power brakes multiply the force a driver applies to the brake pedal using a __________ connected to the engine intake manifold.

53% Answer Correctly

brake line

vacuum booster

cylinder

speed sensor


Solution

Power brakes multiply the force a driver applies to the brake pedal using a vacuum booster connected to the engine intake manifold. This provides for much higher hydraulic pressure in the braking system than could be generated by the driver alone. Antilock brakes (ABS) use speed sensors and adjust the brake pressure at each wheel to prevent skidding and allow the driver more steering control in slippery conditions.


2

__________ 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.

67% Answer Correctly

control arms

suspension springs

ignition coils

shock absorbers


Solution

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.


3

Coolant is circulated through the engine by the:

61% Answer Correctly

radiator

water jacket

water pump

camshaft


Solution

The water pump is driven by a belt connected to the crankshaft and ensures that coolant moves through the engine and radiator.


4

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

57% Answer Correctly

heavy

lean

light

rich


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.


5

Which of the following is the result of the air-fuel mixture exploding instead of burning?

64% Answer Correctly

post-ignition

detonation

pre-detonation

pre-ignition


Solution

Normal combustion in an engine is initiated by a spark plug and results in the complete burning of the air-fuel mixture. If combustion is initiated by a source other than the spark plug, by a hot spot in the cylinder or combustion chamber for example, pre-ignition results. Detonation results if the air-fuel mixture explodes instead of burning. Detonation can cause extremes in pressure in the combustion chamber leading to engine damage.