Lincoln Navigator: Fuel Charging and Controls - Turbocharger - 3.5L EcoBoost (272kW/370PS) / Turbocharger. Diagnosis and Testing

Possible Sources

• Oil leak
• Air cleaner
• Air intake
• Crankcase ventilation system
• Internal engine damage
• Turbocharger

• Start the engine.

• Monitor the exhaust system.

• Inspect the air cleaner.

• Inspect the air intake pipes and hoses for loose connections or leaks.

• Check the crankcase ventilation system for damage and correct operation. REFER to the 303-08 Diagnosis and Testing Crankcase Ventilation procedure for the engine being diagnosed.

NOTE: It is normal for a small amount of combustion gas to pass into the crankcase. This gas is scavenged into the air intake system through the positive crankcase ventilation system, which incorporates a crankcase vent oil separator. Some engine oil, in the form of a vapor, is carried into the air intake system with the blow-by gases (this engine oil also contributes to valve seat durability). This means that oil will collect inside the air intake components and the turbocharger. This is not an indication that the turbocharger oil seal has failed. The turbocharger oil seal will generally not fail unless the bearings fail first, which will cause the turbocharger to become noisy or seize. Do not install a new turbocharger due to oil inside the intake.

• Inspect the inside of the air intake pipes and hoses for excessive oil.

• Remove the air cleaner outlet pipe and CAC intake pipe. Refer to the section 303-12 for the procedure.

• Inspect the compressor wheel for damage.

• Check that the turbine shaft spins free.

• Check for contact marks between the compressor wheel and the housing.

Possible Sources

• Air intake system
• Engine
• Turbocharger

• Compare the customer concern to a known good vehicle. Variations in vehicle options such as engine size, transmission or tire size will sound different. Compare to a vehicle similarly equipped. Compare the vehicle under similar driving conditions, like road test route, APP and load.

• Using the Chassis/Ear, Engine/Ear, and VCMM accelerometers along with the scan tool, locate the source of the noise. REFER to the Engine Noise Identification and Location procedure in the 303-00 section.

• Check the air intake system, air cleaner and CAC components, ducts, pipes and hoses. Check that all components are installed correctly and tight. Check that all components are aligned correctly. Check for damage that could cause an air-intake leak resulting in a noise from the turbocharger(s). For additional information, refer to the 303-12 Intake Air Distribution and Filtering section for the engine being diagnosed.

Possible Sources

• Air cleaner
• Air intake
• Exhaust restricted
• Turbocharger
• Internal engine damage

• Ignition ON.

• Carry out the PCM KOEO and KOER self-tests.

• Inspect the air cleaner.

• Check the air intake system, air cleaner and CAC components, ducts, pipes and hoses. Check that all components are installed correctly and tight. Check that all components are aligned correctly. Check for damage that could cause an air-intake leak resulting in a noise from the turbocharger(s). For additional information, refer to the 303-12 Intake Air Distribution and Filtering section for the engine being diagnosed.

• Check the exhaust system for restrictions or damage. Refer to the 309-00 Exhaust System section for the engine being diagnosed.

• Check the wastegate for damage. Check to be sure the wastegate linkage moves freely.

• Remove the air cleaner outlet pipe and CAC intake pipe. Refer to the section 303-12 for the procedure.

• Inspect the compressor wheel for damage.

• Check that the turbine shaft spins free.

• Check for contact marks between the compressor wheel and the housing.

Possible Sources

• Oil supply tube
• Oil return tube
• Gaskets
• Turbocharger

NOTE: It is very unlikely for the turbocharger to leak engine oil externally. The moving parts of a turbocharger that require oil are contained in a housing with no external sealing surfaces. Pressurized engine oil is supplied to the turbocharger from the engine through an oil supply tube and drains back to the engine sump through an unpressurized return tube. The most likely source of an external oil leak would be from the oil supply or oil return tubes or the gaskets and seals.

• Perform an oil leak inspection. REFER to the Oil Leak Inspection procedure in the 303-00 section for the engine being diagnosed. Visually inspect the oil supply tube for traces of oil. Check the engine and the turbocharger ends. Check for oil running down from other areas of the tube or the engine to locate the source of the leak. Check the oil supply tube gaskets and seals.

• Movement of the vehicle, under hood components or gravity can cause oil leaks to appear in different areas from the source of the oil leak. Follow the trace of the oil leak to the source.

• Visually inspect the oil return tube for traces of oil. Check the engine and the turbocharger ends. Check for oil running down from other areas of the tube or the engine to locate the source of the leak. Check the oil return tube gaskets and seals.