Head Gasket/Intake Manifold Gasket - Leak Diagnosis
Bulletin 86-6-22Date July '86
Ref. No. 86-134-6
SUBJECT: HEAD GASKET LEAKS
MODELS AFFECTED: ALL WITH 3.0L (VIN CODE E AND L) AND 3.8L (VIN CODES A, B, 3, 7, 9) V-6 ENGINES
Some of the above engines may exhibit an oil leak in the area of the block to head joint giving the appearance of a head gasket leak. It is, however, extremely unlikely that an oil leak will occur as a result of a leak in a head gasket. Most often, the leak will be from the corner area of the intake manifold gasket end seals.
Thoroughly cleaning the head and block surfaces in this area with solvent, and then using engine oil dye and a black light to identify the leak source will greatly reduce the possibility of misdiagnosing leaks in this area.