Understanding Preignition and Detonation

What is a common cause of preignition in automotive engines?

• Low octane fuel

• High engine temperature

• Faulty spark plugs

• Excessive engine oil

Which of the following is an effect of detonation in an engine?

• Increased fuel efficiency

• Engine knocking

• Smooth engine operation

• Reduced emissions

How can engine knock be prevented?

• Using lower octane fuel

• Increasing engine load

• Retarding the ignition timing

• Reducing the air-fuel mixture

Which symptom indicates preignition in an engine?

• Delayed engine start

• Engine overheating

• Black smoke from the exhaust

• High-pitched pinging noise

What role does the octane rating of fuel play in preventing preignition?

• Higher octane fuel increases the risk of preignition

• Higher octane fuel reduces the risk of preignition

• Octane rating has no effect on preignition

• Lower octane fuel prevents preignition

Which of the following is a potential consequence of prolonged detonation in an engine?

• Improved engine performance

• Engine damage

• Lower fuel consumption

• Increased engine lifespan

What is a common method to detect engine knock?

• Visual inspection of the engine

• Listening for unusual noises

• Checking the oil level

• Measuring exhaust emissions

Which of the following can cause preignition due to carbon deposits?

• Clean air filter

• Regular oil changes

• Poor fuel quality

• High engine speed

What is the primary difference between preignition and detonation?

• Preignition occurs after the spark plug fires, detonation occurs before

• Preignition is caused by low octane fuel, detonation by high octane fuel

• Preignition occurs before the spark plug fires, detonation occurs after

• Preignition and detonation are the same

Which of the following is a preventive measure against preignition?

• Increasing the compression ratio

• Using a higher octane fuel

• Advancing the ignition timing

• Reducing the engine's cooling system efficiency