A8 Engine Performance Practice Test Questions and Correct Answers

A8 Engine Performance Practice Test Questions and Correct Answers All of the following are tests performed on the PCV system EXCEPT: A. The rattle test B. The snap- back test C. Crankcase vacuum test D. Blowby test - Correct Answer D. The PCV valve should rattle when shaken back and forth. When the thumb is placed over the end of the PCV valve with the engine idling, the plunger should snap back. A water manometer can be used to check the crankcase for vacuum at idle. There is no blowby test that is performed on the PCV system. Which of the following is the LEAST LIKELY cause of ignition module failure? A. An open spark plug wire B. No dielectric grease under the module C. A fouled spark plug D. Loose module mounting screws - Correct Answer C. Faulty secondary ignition components are common causes of ignition module failure. Some modules require the use of dielectric grease to aid in dissipating heat. A fouled spark plug would cause an engine miss, but would not cause the ignition module to fail. Loose module mounting screws will cause the module to fail prematurely. A sequential fuel- injected vehicle has poor fuel economy, yet starts and runs fine. Technician A says the fuel return line may be partially restricted. Technician B says the fuel pressure regulator may be stuck open. Who is correct? A. Tech A B. Tech B C. Both technicians