Today my wife was driving home from work and the car threw a check engine light. I took it for a drive and noticed that when i put the car in neutral it would rev to about 3500 rpm and sit there. I used the search button and founf a few possibilities but nothing much was said about cars with the atx. If i let the car idle it will bounce between 900 and 1100 rpm. I disconected the tps and still had the same problem. I have never changed the pcv valve, maybe that could be the issue. the car has about 50 000 miles.