I have a 2004 WRX w/ 55K miles on it, and recently it has started smoking on start up and when i sit at idle. No power loss or anything, and it doesn't seem like its affecting the power. I just bought the car, and had the oil changed right before I picked it up. It did sit for a few months before I got it. My coolant was low, but it doesn't smell like burning coolant. Oil changed about 300 miles ago. It's cold around here, but even after the car warms up i get intermittent white smoke at idle. No problems whatsoever with oil level or engine overheating. Any ideas?