Loose head bolts causing coolant to escape and overheating.

My initial symptoms were intermittent lack of warm air from the climate system during the winter, and ultimately overheating. I also had bubbles coming from the radiator into the coolant overflow reservoir. I would also have random jumps of the temp gauge. I took it to my dealership in early January. They did a pressure test, topped the coolant off and said everything was ok. Fast forward 3 weeks and I was back in the same boat. I took it back to the dealership and they found the bolts had pulled away from the block. Exhaust gasses were getting past the head gasket into the cooling system. Dealer said they had previously seen issues where chunks of aluminum would come out from the threads when removing the bolts for replacement. This is exactly what happened. The only fix was to replace the short block.