I was driving my 1999 NB GLS a few times today. The first two times I drove it today, it was fine and nothing out of the ordinary. Then when I got home, I turned off the car and there was still a 'running' noise coming from the engine. My husband asked if the car was turned off and it was. I started it again, then turned it off and the noise was still there, then slowly faded. My husband said it sounded like the fan or belts. I drove it twice later that day and there were no problems. Has anyone experienced or heard of this before?