did you ever figure this out?Just wondering if the dealership got your car fixed? I am having the same problems. My CEL came on with the P0171 code(if I rember that one right) anyways I took it to the dealership and they replaced the PCV cap and did something to the water pump. All covered under warranty work. I left the dealership and the next morning my car completely quit on me. I had it towed in and he said something came unplugged and it was fixed. Left once again and the CEL came back on took it back to the dealership and he said it was some kind of gasket on the manifold. Left the dealership and about 10 miles down the road the CEL came on and it was the P0420 code. Took it back yet again and he told me it was the catalytic converter which is not under warranty because my car has 90,000 on it. I did not have $900 so I couldn't fix it. He basically told me to just drive it with the CEL on and it would be fine. The next day I noticed it felt like it was surging when it would shift. So I checked the codes and it was the P0420 & P0299. I just left it at dealership today and I am waiting to see what they say. Could it be something they did to cause the P0420 code? It never had the P0420 untill he worked on it 4 different times so I don't see why I would have to pay the $900 for a catalytic converter to be replaced.