Check engine light
You will need to retrieve the codes from the computer to find that out. Although your vehicle may seem to run fine, there is an emission system related concern that should be addressed. Any of over 100 actuators, sensors and systems needs attention.
You can go to Oriely auto or Autozone and they can hook it up to a computer and tell you or you can buy a simple one for about $50.00 at any auto store or Homedepot.
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