Exam 7: Fuel System and Related Input Sensorsoutput Actuators Diagnosis

Engine surging at idle may be caused by dirty fuel injectors.

How are SFI injectors controlled by the PCM?

An injector balance will identify a restricted fuel injector.

What could cause a fuel-injected engine to run on (diesel) after the vehicle is turned off?

Technician A says that disconnecting the vehicle battery during diagnosis may erase the adaptive strategy from the PCM. Technician B says that a vacuum leak may be misdiagnosed as a fuel delivery problem. Who is correct?

On OBD II systems, failure to clear DTCs will result in the temporary disablement of the non-continuous system monitors.

Why are OBD II vehicles equipped with a fuel system monitor?

What are four components that are supplied voltage by the ASD relay on some vehicles?

During engine operation, the crankshaft position sensor (CKP) identifies crankshaft position, engine speed, and:

If the RPM signal is lost on an electronic fuel-injected vehicle, which of the following conditions will exist?

How does the PCM task manager affect fuel delivery?

On a multiport fuel-injected vehicle, what could cause fuel pressure to remain constant when the throttle is opened rapidly?

What would the engine operational problem be on a vehicle with a defective fuel pump relay if the vehicle has an oil pressure switch wired in parallel to the fuel pump relay?

What effect could a plugged fuel system return line have on the fuel delivery system?

A higher than normal idle speed may be caused by low system voltage.

What is one reason for the requirement of high system fuel pressures in port fuel-injected vehicles?

A rich air/fuel ratio may be caused by low fuel pump pressure.

Disconnecting the vehicle battery during diagnosis may deprogram the radio.

The term injection pulse width refers to:

What is the purpose of the inertia switch in the fuel pump circuit?