Component Tests and General Diagnostics
Turbocharger
Component Tests
Turbocharger Internal Oil Leak Test
NOTE: Some engine oil may be present in the turbocharger compressor inlet and in the air inlet components due to the crankcase breather system.
Check the turbocharger compressor inlet for evidence of oil. If excessive oil is present, this indicates that the failure could be in the engine or turbocharger. Refer to Engine or the following turbocharger check. If excessive oil is found in the turbocharger compressor outlet, check the Charge Air Cooler (CAC) for oil contamination. If contamination is present, flush the CAC (Charge Air Cooler). Refer to Fuel Delivery and Air Induction.
Check the turbocharger turbine outlet for evidence of oil. If excess oil is present in the outlet, remove the turbocharger from the engine and examine the oil supply and return passages in the turbocharger and engine block for restriction. If no restriction is found, install a new turbocharger.
Check for Free Rotation - Off Vehicle
NOTE: The turbocharger must be pre-oiled before carrying out this check.
NOTE: Turbine and compressor wheels must spin freely when turned by hand. No housing contact is permitted.
Inspect the turbocharger compressor and turbine fins for damage. If the compressor or turbine wheel fins are damaged, replace the turbocharger.
Press and rotate the turbocharger shaft, then repeat from the opposite side. If either the compressor wheel or the turbine wheel contacts the housing, the bearings are bad and a new turbocharger must be installed.