?ENGINE LEAK DIAGNOSIS ON TURBOCHARGED V8 ENGINES. When diagnosing an engine oil leak or a coolant leak on turbocharged V8 engines it is necessary to use a borescope to identify if the source of the leak is from under the turbochargers. Engine oil or coolant leaking from the bell housing area or the front timing chain cover area may be caused by the turbocharger itself, a turbocharger oil/coolant feed line or turbocharger oil/coolant return line. Do not remove the transmission and do not dissemble the engine before performing this inspection. If necessary, use engine oil leakage detection dye.