ASVAB Automotive Information Practice Test 379956 Results

Your Results Global Average
Questions 5 5
Correct 0 3.21
Score 0% 64%

Review

1

Too much fuel results in a __________ air-fuel mixture that burns quicker and cooler.

63% Answer Correctly

rich

heavy

lean

light


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.


2

What is the function of the head gasket?

75% Answer Correctly

to seal the brake assembly from external contaminants

to connect the transmission to the drive train

to seal the exhaust system from the drive train

to seal the engine block from the cylinders


Solution

A head gasket is a gasket that sits between the engine block and cylinder heads to seal the cylinders to ensure maximum compression and avoid leakage of coolant or engine oil into the cylinders.


3

The __________ converts pressure on the brake pedal to hydraulic pressure in the brake lines.

60% Answer Correctly

brake knuckle

brake cylinder

master cylinder

brake linkage


Solution

The master (brake) cylinder converts pressure on the brake pedal to hydraulic pressure in the brake lines.


4

The ignition coil is a(n):

63% Answer Correctly

filter

step-down transformer

step-up transformer

amplifier


Solution

The ignition coil steps up the 12 volts available from the battery or alternator to a voltage of 30,000 or more volts at the spark plug. Converting a lower voltage input into a higher voltage output makes the ignition coil a step-up transformer.


5

Ignition timing is measured in number of degrees:

59% Answer Correctly

before top dead center

after bottom dead center

after top dead center

before bottom dead center


Solution

Ignition timing defines the point in time at the end of the compression stroke that the spark plug fires. Measured in number of degrees before top dead center (BTDC), the exact point that the spark plugs initiate combustion varies depending on the speed of the engine. The timing is advanced (the spark plugs fire a few more degrees BTDC) when the engine is running faster and retarded when it's running slower.