ASVAB Automotive Information Practice Test 355496 Results

Your Results Global Average
Questions 5 5
Correct 0 3.11
Score 0% 62%

Review

1

What links each piston to the engine's crankshaft?

72% Answer Correctly

piston ring

cylinder arm

halfshaft

connecting rod


Solution

A connecting rod employs a wrist pin to link each piston to the engine's crankshaft.


2

Just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. This describes which engine stroke?

61% Answer Correctly

power

exhaust

intake

compression


Solution

During the power stroke, just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. The resulting expansion due to combustion pushes the piston back down the cylinder toward bottom dead center.


3

Which of the following is not a function of antifreeze?

54% Answer Correctly

aids heat transfer

lubricates the cooling system

raises the boiling point of water

keeps water from freezing at low temperatures


Solution

Modern car engines are cooled by liquid which circulates through the engine block and cylinder heads absorbing excess heat. This liquid is made up of half water and half antifreeze (commonly, ethylene glycol) which both keeps the water from freezing at low temperatures and raises its boiling point making heat transfer more efficient.


4

Which engine stroke starts with the piston at top dead center?

61% Answer Correctly

compression stroke

power stroke

exhaust stroke

intake stroke


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

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

62% Answer Correctly

allows the use of antilock brakes

provides higher hydraulic pressure in the braking system

utilizes battery power to assist in braking

requires less brake fluid to operate the braking system


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.