The all important Pontiac Connecting Rod Bearings are what allows for the crankshaft to turn and receive the power the pistons are generating. There is a lower and upper connecting rod bearing for each piston in your Pontiac engine.
The connecting rod bearing is not an auto component that you can just walk into an auto parts store and say I have this make and model with this type of engine please give them to me. Each of the connecting rod bearings are made to specific tolerance and clearances that are specific for their application. For these components to be replaced, the clearance or diameter of the cranks shaft at the contact point has to be known for your Pontiac to run and not bind up.
The symptoms of a Pontiac connecting rod bearing starting to falter is when you can hear a thumping sound coming from the bottom of the engine. To positively identify it a metal rod, like a screw driver should be placed against the lower section of the engine block with the technician's ear on the other end. This way the vibration can be clearly heard. The light ticking noise that might also be heard is of the valve train and it is normal for it to be making this higher pitched noise.
The importance of the clearance for each of the connecting rod bearings next to the crankshaft cannot be overstated. If there is insufficient clearance, the engine will lock up. If there is too much clearance, the thumping sound will continue to come from your engine and it will break down in the near future.
These like all other interior engine components on your Pontiac takes a trained profession to replace in most instances, but there are some skilled owners that can handle this repair job.