| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.02 |
| Score | 0% | 60% |
Which of the following receive signals from the powertrain control module (PCM) and carry out its instructions?
actuators |
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joints |
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valves |
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sensors |
Actuators receive signals from the PCM and carry out adjustments needed based on the data the PCM received from the sensors.
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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has two rows of cylinders |
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engine is shorter than an inline engine |
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.
Just before the piston reaches top dead center, the spark plug fires and ignites the compressed air-fuel mixture. This describes which engine stroke?
power |
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compression |
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exhaust |
|
intake |
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.
Ignition timing is measured in number of degrees:
before top dead center |
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before bottom dead center |
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after bottom dead center |
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after top dead center |
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.
Which of the following is not a characteristic of disc brakes?
uses brake shoes |
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uses brake pads |
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newer brake system |
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uses a rotor |
Both drum brake and disc brake assemblies use friction to stop a car's wheels from turning but each do it in a slightly different way. A drum brake assembly uses a large iron drum attached to the wheel and brake shoes that press against the drum to slow the rotation of the drum and, consequently, the wheel. A disc brake assembly employs friction in the same way as a drum brake but instead uses a rotor, also attached to the wheel, and two brake pads that squeeze against the surface of the rotor.