ASE practice test (diesel engine) T2 Already Passed

ASE practice test (diesel engine) T2 Already Passed A diesel engine has excessive oil consumption with no visible oil leaks. Which of these could be the cause? (D) A leaking turbocharger impeller shaft seal Which of ...

ASE practice test (diesel engine) T2 Already Passed A diesel engine has excessive oil consumption with no visible oil leaks. Which of these could be the cause? (D) A leaking turbocharger impeller shaft seal Which of these could be the cause of blue smoke from the exhaust on a vehicle that is not equipped with an exhaust aftertreatment system? (C) Worn piston rings During long uphill pulls, a delivery truck equipped with an engine protection system activates a warning light and buzzer, and the engine derates power. Which of these could be the cause? (C) A partially restricted radiator core Which of these could be the cause of a loud ticking noise on a diesel engine? (A) Excessive valve lash Excessive white smoke is observed coming from the exhaust. Which of these could be the cause? (A) A leaking fuel injector cup A diesel engine has excessive vibration. Technician A says that binding variable geometry turbocharger (VGT) vanes could be the cause. Technician B says that a broken flywheel/flexplate could be the cause. (B) B only The measurement in the setup shown indicates that a new valve is too high. Which of these steps will correct the problem? (D) Remove material from the valve seat. Technician A says that debris in the cylinder head bolt holes can affect head bolt clamping force. Technician B says that using over-stretched cylinder head bolts can affect head bolt clamping force. Who is right? (C) Both A and B Cylinder liner protrusion (height) that is too low can be adjusted by: (C) adding cylinder liner shims. A truck engine has excessive crankcase pressure. During disassembly, the technician notices excessive wear on the cylinder walls and upper piston rings. Which of these could be the cause? (B) A missing engine air filter seal While servicing an engine, the technician finds a slight amount of scoring on the engine side of the flywheel. Technician A says that excessive crankshaft endplay could be the cause. Technician B says that missing bell housing locating pins could be the cause. Who is right? (A) A only The oil pressure gauge indicates low engine oil pressure at higher engine rpm only. Which of these could be the cause? (A) A restricted oil pump pickup screen During inspection, the technician observes engine oil in the coolant expansion tank. This could be caused by a leaking: (D) oil cooler heat exchanger. A diesel engine is being diagnosed for overheating. Once the engine reaches operating temperature, coolant leaks out of the overflow. Which of these could be the cause? (B) A leaking cylinder head gasket While performing a stationary regeneration, the technician notices no significant rise in the diesel oxidation catalyst (DOC) temperature. Which of these could be the cause? (C) An exhaust leak in front of the DOC A diesel engine is being diagnosed for coolant consumption. There are no external leaks and the engine oil does not show coolant contamination. Which of these could be the cause? (D) A failed EGR cooler A diesel engine equipped with an exhaust aftertreatment system emits black smoke from the exhaust. Which of these could be the cause? (C) An internally failed diesel particulate filter (DPF) A diesel engine equipped with a high-pressure common rail (HPCR) fuel system cranks normally, but will not start. Which of these could be the cause? (A) An internally leaking fuel pressure limiting valve An electronic diesel engine has low power only while under load. This could be caused by a: (A) restricted intake manifold pressure sensor port. A diesel engine with a hydraulic electronic unit injector (HEUI) fuel system will not start. During diagnosis, there is no injection control pressure (ICP). Which of these could be the cause? (D) A low engine oil level An electronic diesel engine stalls while driving. After stalling, the engine cranks but will not restart. Technician A says that a failed engine position sensor could be the cause. Technician B says that a failed throttle position sensor could be the cause. (A) A only An electronic diesel engine has low power. No diagnostic trouble codes (DTCs) are stored and the check engine light is not illuminated. Which of these could be the cause? (B) A partially restricted fuel filter An electronic unit injector (EUI) is being replaced. Technician A says that the oil may need to be bled from the gallery before removing the injector. Technician B says that injector calibration codes may need to be programmed in the ECM after installing the new injector. Who is right? (B) B only After connecting to the truck with a laptop that has the correct software application, the technician observes a failure to communicate message. The truck runs normally and no warning lights are displayed on the dash. Which of these could be the cause? (D) A poor connection at the 9-pin diagnostic connector A truck has an "Engine Coolant Temperature (ECT) Sensor Signal Circuit High" DTC. During diagnosis with the key ON/engine OFF, the technician observes the digital multimeter (DMM) measurement shown. Which of these could be the cause? (B) An open circuit at X A truck has an overcharging condition. Technician A says that high resistance in the alternator case ground could be the cause. Technician B says that high resistance in the alternator remote sensing circuit could be the cause. Who is right? (B) B only A truck has a no-crank condition. With the ignition switch in the START position, the technician observes the digital multimeter (DMM) measurement shown. The cause could be an open circuit at: (C) Y. The compression brake functions but performance is weak on a truck equipped with an electronic diesel engine. Which of these could be the cause? (D) Misadjusted slave pistons