ASE A8 - Engine Performance Vehicle Practice Questions

A vehicle is experiencing a rough idle. What could be a cause if the fuel trim is within specs?

• AA. Bad catalytic converter
• BB. Dirty fuel injectors
• CC. Leaking exhaust system
• DD. Faulty spark plugs

During an emissions test, a vehicle fails due to high hydrocarbon levels. What is the likely issue?

• AA. Faulty oxygen sensor
• BB. Low battery voltage
• CC. Exhaust leak
• DD. Dirty air filter

If a vehicle's engine runs smoothly when cold but exhibits issues when it warms up, what is the likely cause?

• AA. Weak ignition coil
• BB. Fuel leak
• CC. Clogged radiator
• DD. Bad thermostat

What could cause engine misfire in a vehicle that has recently had engine repairs?

• AA. New air filter
• BB. Disconnected battery
• CC. Incorrectly installed spark plug
• DD. Low oil level

If a vehicle has a decreased fuel economy and an increase in exhaust smoke, what might you suspect?

• AA. Malfunctioning MAF sensor
• BB. Overfilled fuel tank
• CC. Faulty fuel pressure regulator
• DD. Dirty fuel injector

After replacing the fuel pump, the vehicle still has starting issues. What should you check next?

• AA. Fuel injector operation
• BB. Battery terminal voltage
• CC. Oil level
• DD. Camshaft position sensor