Turbocharger Internal Oil Leak Test
WARNING: This page does not describe the selected car, but rather 16 other vehicles, including the 1996 Ford RV Cutaway, 1996 Ford Pickup, 1996 Ford F-Super Duty, 1996 Ford Econoline, and 1996 Ford Cutaway. However, it is still accessible from the selected car via links, so may be relevant.
Check the turbocharger compressor inlet for evidence of oil. If excessive oil is present, this indicates that the failure is in the engine, not in the turbocharger; for additional information, see appropriate SELF-DIAGNOSTICS article.
Check the turbocharger turbine outlet for evidence of oil. If oil is present in the outlet, remove the turbocharger from the engine and examine the oil supply and return passages in the turbocharger pedestal and engine block for restriction. If no restriction is found, replace the turbocharger.