ASVAB Automotive Information Practice Test 440785 Results

Your Results Global Average
Questions 5 5
Correct 0 3.09
Score 0% 62%

Review

1

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

64% Answer Correctly

post-ignition

pre-ignition

pre-detonation

detonation


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.


2

Engines with radial cylinder configurations are most common in:

59% Answer Correctly

tank engines

train engines

aircraft engines

heavy truck engines


Solution

A radial arrangement places cylinders in a circle around the crankshaft and is used almost exclusively in aircraft engines.


3

The fuel injectors are fed fuel by the:

65% Answer Correctly

electric fuel pump

powertrain control module

fuel pressure regulator

fuel return line


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.


4

Control arms connect a vehicle's suspension to the frame. The connection to the wheels is through:

71% Answer Correctly

bushings

ball joints

pins

knuckles


Solution

Control arms (upper and lower) connect a vehicle's suspension to the frame. The connection to the wheels is through ball joints which allow the control arms to turn and move up and down simultaneously. The frame connection uses bushings.


5

Which of the following is not an advantage that disc brakes have over drum brakes?

50% Answer Correctly

provide a larger contact area

use less brake fluid

are more easily cooled

provide more braking force


Solution

Brakes utlize friction to slow vehicle tires. Drum brakes employ a cast iron drum that roates with the vehicle axle. When hydraulic pressure is applied to the brake assemblies at the wheels, internal pistons expand and push brake shoes outward into contact with the brake drum slowing the rotation of the axle. More powerful disc brakes operate by pinching a rotating disc betweeen two brake pads and allow for a larger surface area to contact the disc, provide more force, and are more easily cooled.