If the sealing effectiveness of the Pontiac cylinder head gasket set is compromised in any way, damage to the engine will begin to occur. This can be a breach in the seals between the water or oil galleys along with the compression chambers in the engine block when the cylinder head gasket splits or cracks. When a breach between the oil galley and the combustion chamber occurs in the cylinder head gasket set, oil will leak down into the cylinder. This is be noticed by anyone looking at the vehicle when it is running because blue oil smoke will be coming from the tail pipe. Pressure can also make its way from the combustion chamber to the crankcase which will then be pushing the oil dip stick out of its holder on your Pontiac engine. If the seal between the coolant and oil galleys is breached in the cylinder head gasket set, then the engine oil will begin to foam. This is the most dangerous condition your engine can experience. Coolant is not a good lubricant, and the bearings along with other internal components will then have excessive wear being exerted on them. You can tell when a Pontiac cylinder head gasket set is no longer sealing the contact area between the head and the block of the engine when the water jacket is now leaking small amounts of coolant into the combustion chamber. With coolant entering the combustion chamber in your Pontiac engine, white smoke is now exiting the tail pipe. This white smoke is coolant being turned to water vapor. If any of these conditions are occurring then the replacement of the cylinder head gasket set must be done in a very short time frame or your Pontiac engine will be severely damaged.