Check engine light on
Get the codes pulled, most parts stores can do this and it's free, write them down and repost them back here and someone will jump in and help you with further diagnosis. If I were to guess after 10 years, I would say that your O2 sensors are due for replacement, and the codes will confirm that, but just don't run down and buy them until you have verified that is the problem. It could be something totally different.
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