Quiz 6

If the noid light does not flash when checking an electronic fuel injector's feed circuit, the cause of the problem may be all of the following:

- an open in the wiring - a bad connection - a control module problem

If the noid light does not flash when checking an electronic fuel injector's feed circuit, the cause of the problem may be all of the following except:

- a faulty injector

Which of the following is a subsystem of the gasoline injection system?

- Fuel - Sensor - Air

Atmospheric pressure, at sea level, is ____ psi.

14.7

When installing a new oxygen sensor, coat the threads with _____.

Anti-seize compound

An injector balance test shows a below normal pressure drop on one injector. Tech A says that the injector is bad and should be replaced. Tech B says to try running cleaning solution through the injector. Who is right?

B only

Tech A says a fuel injector pulsed flow test measures steady or maximum fuel flow with the injector pintle and nozzle held fully open. Tech B says injector maximum flow test fires an injector several times with a normal pulse width to check pintle response. Who is right?

B only

A pressure gauge connect to the fuel pressure test fitting (Schrader valve) shows a pressure lower than spec. Tech A says that the low pressure is likely to be caused by a faulty fuel pressure regulator. Tech B says the fuel pump is possibly at fault. Who is right?

Both A and B

A clicking sound from an injector indicates that it is faulty and should replaced. (T/F)

False

A failed intake air temperature sensor will cause a severe drop in fuel mileage. (T/F)

False

Low impedance fuel injectors require high voltage for rapid operation. (T/F)

False

Checks exhaust gas for combustion efficiency.

Oxygen sensor

A frequent cause of fuel injection system problems is high resistance due to corrosion at the terminals on the wiring harness. (T/F)

True

An impedance test indicates how quickly the injector will open to spray fuel. (T/F)

True

In a direct injection system, the fuel is forced into the combustion chamber itself. (T/F)

True

In a modern gasoline direct injector systems, it is possible to control engine speed without a throttle valve in the intake tract. (T/F)

True

One reason for a poor injector spray pattern is a dirty nozzle. (T/F)

True

Throttle valves are used on gasoline engines, but not on diesel engines. (T/F)

True

You should not use silicone-based sealer on or around the exhaust system components. (T/F)

True

Scan tool readings made with the engine running at curb idle speed and full operating temp. are typical circuit values called _____.

idle live readings

The ______ is not one of the subsystems of an electronic fuel injection system.

idle solenoid system

The sensor used to detect engine speed is the _______.

throttle position sensor