ASE A8 Quiz 2

Tech A says to complete the manufacturer's recommended drive cycle after replacing the engine control module. Tech B says completing a drive cycle include driving the vehicle at certain speed for a specific time. Who is correct?

• Tech A

• Tech B

• Both

• Neither

A vehicle as a momentary hesitation only during acceleration. The MOST likely cause of this condition is a faulty:

• Exhaust Gas Recirculation (EGR) Valve

• Oxygen Sensor

  (O2)

• Positive Crankcase Ventilation

  (PCV) valve

• Throttle Position Sensor (TPS)

A four-cylinder EFI engine has a DTC indicating insufficient EGR Flow. The EGR solenoid is found to be faulty. This EGR fault will cause an increase in what type of emissions?

• CO

• HC

• CO2

• NOx

A vehicle suffers a sudden drop in fuel economy. The variable valve solenoid is commanded on, and there is no change in engine operation. Tech A says to inspect the variable valve system's oil control valve. Tech B says contaminated engine oil can result in this condition. Who is correct?

• Tech A

• Tech B

• Both

• Neither

An engine's control module uses speed-density method to estimate airflow into the engine. Tech A says this engine relies on the MAP and IAT sensors to adjust the air-fuel ratio. Tech B says the MAP sensor indicates manifold pressure to the ECM. Who is correct?

• Tech A

• Tech B

• Both

• Neither

There is a misfire at the #3 cylinder of a COP ignition system. A voltage test indicates no power at the Bat+ terminal of the coil's plug. Which of these could be the cause?

• Resistance in the primary circuit

• Resistance in the secondary circuit

• A leak in the secondary insulation

• An open between the coil and its 12 volt source

The OBD II Enhanced Evaporative Emissions Monitor has illuminated the check engine light with fault code P0457, indicating a gross leak has been detected. Which of the following is MOST likely the cause of this leak?

• A crimped closed vent hose

• A saturated canister

• A stuck closed purge valve

• A loose fuel filler cap

A vehicle with a four-cylinder EFI engine has a clogged catalytic converter. Scan tool data indicates the engine has a Long Term Fuel Trim (LTFT) of -19% at idle. Tech A says a LTFT of -19% means the ECM is adding fuel to the air-fuel mixture. Tech B says a rich air-fuel mixture can cause the catalytic converter to overheat. Who is correct?

• Tech A

• Tech B

• Both

• Neither

A vehicle has a fuel trim of -5 % at idle and -25% at cruise. Scan tool data indicates a steady oxygen sensor output of 800Mv. When a vacuum hose is disconnected from the intake manifold, there is no change in the oxygen sensors voltage signal. This condition is caused by:

• An intake manifold leak

• A faulty throttle position sensor

• A faulty oxygen sensor

• A kink in the fuel return line

A scan indicates that an engine's air-fuel ratio is rich. Which of the following would result in this condition?

• A faulty ECT Engine Coolant Temperature Sensor

• A faulty thermostat

• Both

• Neither