I would like your input on a problem I have with this car. (06 STI) When I change the oil, the next day and for approx. a week after, every morning it has valve train noise. I park it on an unlevel surface all the time at night. I park on level at work and when I start the car to go home no valve noise with fresh oil change. The valve train noise appears to go away after oil gets one week or so old, even when car is parked on unlevel surface. Oil light behaves consistently at all times, it goes out instantly after car starts. I have tried both conventional and synthetic oil. Also what is the best oil for this motor?
Please let me know what you think, Your opinion would be greatly appreciated.