I have an automatic, I don't drive it hard, but I don't baby it either. I don't know if it has ever had a valve adjustment. When I bring it to the Acura service center, they just do what the records say it needs. They are the ones that told me it's a purge control solenoid. But they also said it is perfectly normal and they can't fix it. I just can't believe that. I've had it since 2800 miles and always did what ever maintenance they suggested.