ASVAB Automotive Information Practice Test 590571 Results

Your Results Global Average
Questions 5 5
Correct 0 3.26
Score 0% 65%

Review

1

What is the function of the head gasket?

75% Answer Correctly

to seal the engine block from the cylinders

to seal the brake assembly from external contaminants

to seal the exhaust system from the drive train

to connect the transmission to the drive train


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.


2

Another name for the powertrain control module is the __________ control unit.

54% Answer Correctly

electrical

universal

engine

transmission


Solution

The main computer or powertrain control module (PCM) uses pre-programmed software to analyze the input received from sensors and produce output signals to adjust vehicle performance and operation. (Engine control unit (ECU) is another name for the PCM.)


3

Which of the following statements about v-type cyllinder arrangement is false?

65% Answer Correctly

common in motorcycles, cars, and trucks

has an odd number of cylinders

engine is shorter than an inline engine

has two rows of cylinders


Solution

A v-arrangement has two rows of cylinders in a V-shaped block with a crankshaft at the bottom of the V. Any even number of cylinders is possible in this configuration from the V-2 that's commonly used in motorcycles up to V-12 or bigger for large trucks. The V design produces a shorter engine than an in-line cylinder configuration and allows for better air-fuel distribution.


4

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

61% Answer Correctly

power stroke

exhaust stroke

compression 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

The stoichiometric ratio is approximately:

70% Answer Correctly

14.7

1:1

14.7:1

1:14.7


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.