| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.26 |
| Score | 0% | 65% |
What is the function of the head gasket?
to seal the engine block from the cylinders |
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to seal the brake assembly from external contaminants |
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to seal the exhaust system from the drive train |
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to connect the transmission to the drive train |
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.
Another name for the powertrain control module is the __________ control unit.
electrical |
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universal |
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engine |
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transmission |
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.)
Which of the following statements about v-type cyllinder arrangement is false?
common in motorcycles, cars, and trucks |
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has an odd number of cylinders |
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engine is shorter than an inline engine |
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has two rows of cylinders |
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.
Which engine stroke starts with the piston at top dead center?
power stroke |
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exhaust stroke |
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compression stroke |
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intake stroke |
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.
The stoichiometric ratio is approximately:
14.7 |
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1:1 |
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14.7:1 |
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1:14.7 |
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.