HEAD GASKET COOLANT LEAKS DYE AND BLACK LIGHT TEST

VEHICLES AFFECTED: ALL MODELS WITH 3.OL (VIN CODE E & L) AND 3.8L (VIN CODES A, B, 3, 7, 9) V-6 ENGINES

When diagnosing any of the above engines for possible head gasket leaks, care should be taken to inspect the corner area of the intake manifold gasket and seals prior to removing the cylinder head for gasket replacement.

Leaks from this area will run down the block to head joint giving the appearance of a head gasket leak.

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.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.