This happened to me yesterday. I parked my car after a ride and as I shifted to P (93se auto), the engine noise appeared too loud. I left the motor running, lifted up the hood, and couldn't locate the exact place for the higher noise. It didn't have a irregular noise, just louder than normal. I then looked at the rpm gauge, and it was at about 1700, if you ever observe it then you know it's usually about 700-800 when the car is standing still and in P mode. Today it was back to normal noise and rpm at 700-800 again. Anyone familiar with the symptom?