Recognizing your mileage is too high, I wanted to post as to let others know that major emissions systems are covered under warranty by the EPA via the Clean Air Act for 8 years or 80K miles regardless of mfg warranty. Worse, the manufactures often don't know, or don't want the hassle and will try to get you to pay for the repairs.
I had an Accord that had the check engine light many times to which I brought in, they would clear it and sent me on my way. I noticed it more frequently after the Honda warranty was up and since I was giving the car to my mom, I borrowed a friends computer to determine the code. The code indicated a possible bad catalytic converter. Brought it in without telling the dealer I saw the code, and magically they finally saw it as well. (It always is easy to find when out od warranty for some reason...) They first tried to charge me for sensors and a CC, and denied knowledge of warranty until I told them to do more research, telling them the law/warranty; even providing a link. They called back and still wanted me to pay for the sensors, but I argued that they had to be replaced once the CC was replaced per their very statement, so it should be included, not to mention that I had brought this in numerous times during warranty and their final response was, if it stays on more than a week, come back in. Ultimately it saved me $1700, and by not bringing up the warranty during their initial inspection, they made a mistake in telling me the sensors needed to be replaced per the CC. Some sensors/components are not included in the warranty if changed independently.
Anyway, there are a lot of people who are not aware of this warranty/law, and the dealer still tries to stick them with the bill. You have to be vigilant and show them documentation. Seems odd as you would think they are aware of this. My guess is they are, but it must be a hassle and they clearly get more money from the consumer, than the government... Either way, even when people are aware of the warranty, many still have issues with the dealer trying to charge them for components written within the warranty...