Why does my 1999 Park Avenue run fine and quiet for 20 - 25 minutes of driving, but then a pulsing squeal starts? After that, a high pitched squeal. Facing the engine, the noise comes from lower right side. Any ideas? Took it to a family member and he thought it was the transmission pump. There's no burning smell or real shifting issues. He also noticed the lines about the lower front of the engine were quite hot after a short drive. There was no strong air pressure coming out of my exhaust pipe, just heat, so he felt a new muffler was needed, too. I've also sunk $1100 in it so far to get it running after sitting for a year, now this!