Chap 32 33
Technician A says engine vacuum is normally measured in inches of mercury. Technician B says a pressure gauge that is labeled psig will read 14.7 psi at sea level. Who is correct?
A only
Technician A says proper tuning of the exhaust pipe .......... could create a partial vacuum that helps pull out exhaust gases out of the cylinder. Technician B ........................................., this helps exhaust gas efficiency. Who is correct?
A only
Technician A says the EVAP monitor for an OBD-II system determines whether there is a sufficient purge flow by varying the purge solenoid duty cycle will monitor the change in the STFT. Technician B says the canister bent solenoid must be open during EVAP pressure test in portion of the monitor. Who is correct?
A only
The AIR system reduces
Hydrocarbon build up
The function of the air bypass valve in a modern supercharger is to
reduce air handling losses or drag while the engine is running at idle
A digital EGR valve has up to ____________ solenoids
three
NOx emissions are caused by nitrogen and oxygen uniting at cylinder temperatures above
2,500 F
A turbocharged engine is running with 10 psi of turbo boost at what pressure is the air being fed into the engine when the engine is operating as sea level?
24.7 psi
Which of the following statements concerning superchargers is not correct?
A bypass is designed into the system to allow the supercharger to idle along when extra power is not needed.
Technician A says Diesel fuel is a light fuel oil and is denser and heavier than gasoline. Technician B says diesel fuel is not as good as a lubricant as gasoline therefore the wear on piston rings and cylinder walls are greater in diesel engines. Who is correct?
A only
Technician A says the catalytic converter maybe tested with a pyrometer. Technician B says the converter maybe tested using an exhaust gas analyzer. Who is correct?
Both
Technician A says the differential pressure feedback EGR sensor can determine the amount of gas flowing through the EGR valve by measuring the pressure put across its surface. Technician B says some EGR valves have an NPC resistor to measure exhaust gas temperature.................
Both
In a turbocharger the turbine and air compressor will rotate at speeds up to
10,000 rpm
Engine vacuum maybe used to operate the
All of the above
Which of the following is not a metal used for producing the manifold
Aluminum
All of the following statements concerning ____________ turbine type turbochargers are true except...
B
An advanced evaporative engine system with OBD-II can detect a leak in the hoses, lines, fuel tank, or gas cap as small as
B
Technician A says a vacuum leak results in less air into the engine which causes a richer a/f mixture. Technician B says a vacuum leak in the system can cause the engine to run poorly. Who is correct?
B only
Technician A says that the emission vacuum schematic for the vehicle can only be found in the factory service manual. Technician B says the emissions vacuum schematic is given on an under hood decal. Who is correct?
B only
Technician A says the a/f ratio ................... CO is increased. Technician B says CO is ................ colorless, odorless, and ..................
B only
Before replacing an exhaust system component. Technician A soaks all old connections with penetrating oil. Technician B checks the old systems routing points for clearance to install the parts. Who is correct?
Both
Exhaust manifold gaskets are being discussed. Technician A says many modern vehicles are being built without gaskets between cylinder heads and exhaust manifolds. Technician B says when performing any service on these engines when removing a gasket from the heads a new gasket should be installed. Who is correct?
Both
Technician A says a misfire is caused by incomplete combustion. Technician B says an excessively lean air fuel mixture will result in cylinder misfire and high HC emissions. Who is correct?
Both
Technician A says a three way catalytic converter oxidizes Carbon monoxide and HC into carbon dioxide and water. Technician B says a TWC reduces NOx air into nitrogen and carbon dioxide. Who is correct?
Both
Technician A says oil int he PVC and air filter can occur if the PVC valve is restricted or plugged up. Technician B says oil in the throttle body ........................
Both
Technician A says that the intake manifold that delivers both air and fuel both carb or TDI is designed to cause turbulence so the air and fuel mix well while their being delivered to the cylinders. Technician B says that in an air only intake manifold (PFI), the length of the runners are designed to achieve the best performance during the particular range of the engine speed. Who is correct?
Both
Technician A says the OBD-II EVAP system leak test monitor will not run if fuel level is too high. Technician B says the monitor will not run if the fuel level is too low. Who is correct?
Both
Technician A says the air filter was designed to prevent engine fire and engine back fire. Technician B says the air filter was also designed to reduce the amount of intake air. Who is correct?
Both
Technician A says the bearings in a turbocharger are cooled by engine oil. Technician B says the turbocharger bearings are cooled by engine coolant. Who is correct?
Both
Which of the following can not cause...........
CO
The catalytic converter is being tested with a pyrometer. The outlet temperature is 100F higher than the inlet temperature, what is indicated?
Converter is ok
The boost pressure of a supercharger is proportional to
Engine speed
Technician A says the engine should idle over to 20 to 127 after being ran to allow the turbocharger time to cool. Technician B says if a vehicle hasn't been driven for a few days start the engine up and then rev it up to 2,000 RPMs to push old oil out of the turbocharger. Who is correct?
A only
Technician A says the main advantage to a turbocharger is that it allows for an increase of power without a substantial decrease in fuel economy. Technician B says the use of exhaust gas to drive the turbocharger robs power from the engine when the vehicle is driven at low speeds. Who is correct?
A only
Technician A tests for a restricted exhaust with an exhaust pressure gauge. Technician B uses the digital infrared pyrometer. Who is correct?
A only
detonation sensors are being discussed. Technician A says that most detonation sensors are under a lot of............. . Technician B says detonation sensors are mounted near the exhaust. Who is correct?
A only
Variable intake manifolds for engines with port fuel injection are being discussed. Technician A says at low speeds the air travels through the short or large ............ runner. Technician B says they deliver more power at high speeds. Who is correct?
B only
While discussing EGR systems with differential pressure feedback sensor. Technician A says PPFE sensors sends a signal to the PCM In relation to the intake manifold pressure. Technician B says That the PCM can make corrections to the EGR flow if the actual flow doesn't match the desired flow. Who is correct?
B only
Technician A says the catalytic converter breaks down HC and CO2 a relatively harmless by-product. Technician B says OBD-II regulations call for a monitering system that looks at the effectiveness of the converter. Who is correct?
Both
Technician A says the operation of the wastegate is controlled indirectly by back pressure. Technician B says the wastegate is controlled by the PCM. Who is correct?
Both
Technician A says the production of CO2 is directly related to the amount of fuel consumed therefore more fuel efficient engines produce less CO2. Technician B says imposing new fuel economy ...................
Both
Technician A says turbocharging uses the heat energy in the engines exhaust gasses to pressurize intake air. Technician B says Supercharging relies on the rotation of the engine to compress the air. Who is correct?
Both
technician A says there ..................... at a cruising speed with a very light load. Technician B says instead of an EGR valve some engines use a ....... to trap some exhaust gasses in the combustion chamber. Who is correct?
Both
All of the following are considered harmful gasses accept
O2
Which of the following is not part of the OBD-II Evaporative Control System?
Thermal vacuum valve
What is the first step in turbocharger inspection?
Turn it on and listen
What manages turbo output by controlling the amount of exhaust gas entering the turbine housing?
Wastegate
A restricted exhaust system can cause
all of the above
