Pinpoint Test A: Blue Smoke From Exhaust
WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
- Possible Sources
- Oil leak
- Air cleaner
- Air intake
- Crankcase ventilation system
- Internal engine damage
- Turbocharger
- A1 CHECK THE EXHAUST
- Start the engine.
- Monitor the exhaust system.
Is blue smoke noticeable from the exhaust system?
Yes GO to A2 No INSPECT for external oil leaks. REFER to: Engine - Gasoline . - A2 CHECK THE AIR CLEANER
- Inspect the air cleaner.
Is the air cleaner clogged?
Yes REPLACE the air cleaner. Check the system for normal operation. No GO to A3 - A3 CHECK THE AIR INTAKE PIPES AND HOSES
- Inspect the air intake pipes and hoses for loose connections or leaks.
Were any loose connections or leaks found from the air intake pipes or hoses?
Yes REPAIR or REPLACE the intake air system. No GO to A4 - A4 CHECK THE CRANKCASE VENTILATION SYSTEM
- Check the crankcase ventilation system for damage and correct operation. REFER to Diagnosis and Testing CRANKCASE VENTILATION procedure for the engine being diagnosed. Refer to the appropriate Engine System article for the procedure.
Is the crankcase ventilation system damaged?
Yes CLEAN, REPAIR or REPLACE the crankcase ventilation components. No GO to A5 - A5 CHECK THE AIR INTAKE PIPES AND HOSES FOR EXCESSIVE OILNOTE: 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.
Is excessive oil noticeable?
Yes GO to A6 No To diagnose internal engine damage. REFER to: Engine - Gasoline . - A6 CHECK THE TURBOCHARGER
- Remove the air cleaner outlet pipe and CAC intake pipe.
- Inspect the compressor wheel for damage.
- Check that the turbine shaft spins free and is not loose in the housing.
- Check for contact marks between the compressor wheel and the housing.
Is the turbocharger damaged?
Yes INSTALL a new turbocharger. No REFER to ENGINE SYSTEM - GENERAL INFORMATION Diagnosis and Testing to diagnose internal engine damage.