Car Mechanics Multiple Choice Questions

What is the purpose of a starter motor in a car?

• To charge the battery

• To start the engine

• To cool the engine

• To power the lights

A diesel engine relies on which of the following to ignite the fuel?

• Spark plugs

• Compression

• Electric charge

• Carburettor

The stoichiometric air-to-fuel ratio for a petrol engine is approximately?

• 10:1

• 12:1

• 14.7:1

• 16:1

What component delivers fuel directly into the engine in a modern car?

• Carburettor

• Fuel pump

• Injector

• Turbocharger

What is the main purpose of an alternator in a car?

• To start the engine

• To power the air conditioning

• To convert mechanical energy to electrical energy

• To increase fuel efficiency

Which of the following is a characteristic of straight cut gears?

• Quiet operation

• High durability under heavy load

• Self-lubricating

• Used for reverse gear in most cars

What is the function of the rear differential in a car?

• To change gear ratios

• To allow wheels to rotate at different speeds

• To control braking force

• To increase engine efficiency

What is a common symptom of a failing slave cylinder in a car?

• Overheating engine

• Difficulty changing gears

• Loss of braking power

• Decreased fuel efficiency

Helical gears are often used in gearboxes because they:

• Are cheaper to manufacture

• Operate quietly

• Provide a 1:1 gear ratio

• Are used exclusively in reverse gears

What is the main role of compression in a diesel engine?

• To improve fuel economy

• To ignite the fuel

• To cool the engine

• To reduce emissions