2 weeks after I bought it, the driver side power window stopped working. The dealer fixed it under warranty without any problems. Other than routine maintenance, I have had little trouble with this car.
This is a great car. It's very reliable. We have driven it from South Carolina to Arkansas and back 3 times. I have always wanted a Grand Prix and I love this car. I don't think I'll be getting rid of it in the near future. It's also very comfortable. My husband is 6'5" and even he can fit comfortably in this car.
The problem with the window is just the beginning. I also have a 1999 Grand prix. I am the original owner and I have replaced eight window regulators. Pontiac used plastic at the retaining points and when they get hot they break allowing the window to slide into the door. Pontiacs response to this has been Oh well, your car has 80,000 miles on it. Even though three of the eight windows were repaired under warranty, the first at 12,000 miles. It is a poorly designed piece of equipment and Pontiac will not stand behind their product. I have also replaced numerous fuel injectors (at least once for each one). I WAS a lifelong GM owner, this car has me looking for a Nissan or Toyota.