WorksheetsLV07B
Total questions: 15
Worksheet time: 8mins
In an electronic fuel injection system under idle conditions a fuel pressure regulator will:
not return any fuel back to the fuel tank
return fuel dependent upon ambient air pressure
return minimal quantities of fuel back to the fuel tank
return most of the delivered fuel back to the fuel tank
An engine will start and idle but the RPM does not increase when the throttle is depressed. The most probable cause of this would be a:
defective lambda sensor
carbon build-up in the engine
defective enrichment device
blocked exhaust system
Engine piston slap will be more evident when:
the engine is running a very weak mixture
the engine is started from cold
the engine is at normal operating temperature
the engine is on overrun
Which one of the following methods would be used when checking an electronic fuel injector for serviceability?
An ammeter check on circuit resistance
A voltmeter check on component current
An ohmmeter check on circuit voltage
An ohmmeter check on component resistance
An engine 'knock' sensor is also known as a:
manifold absolute pressure sensor
zirconium dioxide sensor
piezoelectric accelerometer sensor
variable capacitance sensor
A sequential fuel injection system:
delivers fuel to all the cylinders at once
delivers fuel to each cylinder in turn
delivers fuel through a single throttle body injector
delivers fuel at 5 second intervals
A gas analyser test on an engine shows a lower CO and a normal HC reading. Which one of the following is the most likely fault?
Engine carbon build up
Defective coolant temperature sensor
Exhaust system leak
Blocked air filter
Which type of waveform will an inductive type sensors produce?
Square wave
Saw tooth wave
Sine wave
Cosine wave
Which one of the following components would you check for 'ovality'?
Crankshaft webs
Cylinder bores
Cylinder heads
Big end shells
In an air conditioning system the function of the condenser is to:
separate gas and liquid
regulate refrigerant flow
radiate heat
isolate the compressor
After rectifying an engine fault you need to road test the customer's vehicle. Before you start the test it is essential that you:
complete the job card with all details concerning the vehicle repair
ensure your work bay is tidy and all tools have been put away
check that you hold the correct driver's license for the vehicle
check the vehicle's tyre pressures, oil level and windscreen washer fluid
Which one of the following is the most likely symptom of an inlet manifold air leak?
Engine cutting out at high engine revs
Engine juddering
Engine misfire
Engine stalls at idle speed
The FIVE basic inputs into an electronic fuel injection closed loop (mass air flow) system are:
RPM, airflow, throttle position, EGR sensor, oxygen sensor
RPM, air temperature, throttle position, oxygen sensor, airflow
RPM, manifold pressure, idle speed control valve, water temperature, oxygen sensor
RPM, airflow, throttle position, water temperature, oxygen sensor
What is meant by the 'flash point' of a fuel?
The ability of a fuel to burn at low temperatures
The anti-knock index number of a fuel
The critical temperature at which the fuel will ignite
The measure of how quickly fuel vaporises
When the starter motor is operated by the key, the engine rotates slowly. The most likely fault is:
retarded ignition timing
low cylinder compression
corroded earth strap
open circuit starter relay
