ASVAB Automotive Information Practice Test 469246 Results

Your Results Global Average
Questions 5 5
Correct 0 3.13
Score 0% 63%

Review

1

Which of the following is a common firing order for four-cylinder engines?

66% Answer Correctly

1-3-4-2

1-2-3-4

3-1-2-4

4-3-2-1


Solution

The stroke cycle of an engine is governed by the crankshaft which serves to regulate the firing order of the cylinders. All cylinders are not on the same stroke at the same time and correct firing order is important to balance engine operation and minimize vibrations. A common firing order for four-cylinder engines is 1-3-4-2 which indicates that cylinders 1 and 3 fire (power stroke)together and cylinders 4 and 2 fire together.


2

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

54% Answer Correctly

cylinder

speed sensor

vacuum booster

brake line


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.


3

What is the pimary advantage of using power brakes on a vehicle?

63% Answer Correctly

utilizes battery power to assist in braking

provides higher hydraulic pressure in the braking system

requires less brake fluid to operate the braking system

allows the use of antilock brakes


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.


4

What is the name of the proper ratio of air to fuel necessary so that an engine burns all fuel with no excess air?

62% Answer Correctly

combustion ratio

ignition ratio

residual ratio

stoichiometric ratio


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

A __________ is designed to drive a pair of wheels while allowing them to rotate at different speeds.

69% Answer Correctly

CV joint

transfer case

differential

half shaft


Solution

A differential is designed to drive a pair of wheels while allowing them to rotate at different speeds. A transaxle is a transmission that incorporates the differential in one package. Most front-wheel drive cars use a transaxle while rear-wheel drive cars use a transmission and separate differential connected via a drive shaft. The differential is incorporated into the drive axle which splits engine power delivered by the drive shaft between the two drive wheels. All-wheel drive cars typically use a transaxle that includes an output shaft to the rear differential.