Engine Actuators Quiz

What is the primary function of a petrol injector in an engine management system?

• To ignite the air-fuel mixture

• To atomize and inject fuel into the intake manifold or combustion chamber

• To measure air intake

• To regulate exhaust emissions

Which type of waveform does an oscilloscope show for a petrol injector in operation?

• Square wave

• Pulse width modulation (PWM)

• Sine wave

• Steady voltage

What is a common symptom of a failing petrol injector?

• Misfire or rough idle

• Increased oil pressure

• High engine temperature

• Improved fuel economy

How can you test the resistance of a petrol injector?

• Use an oscilloscope

• Use a multimeter to measure resistance across the injector terminals

• Check for signal with a logic probe

• Use a pressure gauge

What is the best way to measure resistance across the injector terminals?

• Use a logic probe

• Use a multimeter

• Check for signal with a logic probe

• Use a pressure gauge

What could cause an injector to deliver insufficient fuel?

• Low engine temperature

• Clogged injector nozzle

• High fuel pressure

• Short duty cycle

What is a key difference between diesel injectors and petrol injectors?

• Diesel injectors require lower pressure

• Diesel injectors operate at high pressure to inject directly into the combustion chamber

• Diesel injectors use spark for ignition

• Diesel injectors only work in two-stroke engines

What kind of signal pattern is typically shown on an oscilloscope for a diesel injector?

• Pulse width modulation (PWM)

• Direct current

• Square wave

• Alternating current

Which tool is commonly used to test diesel injector spray patterns?

• Multimeter

• Diesel pop tester

• Oscilloscope

• Logic probe

What might be the result of a faulty diesel injector?

• Enhanced engine power

• Black smoke from exhaust

• Reduced oil temperature

• Decreased fuel economy