Why is my check engine light on but car runs fine?
A solid CEL with no driveability change usually points to one of the slow-developing emissions faults: a loose or bad gas cap (P0440/P0457), a lazy O2 sensor (P0420 catalyst efficiency), or a small EVAP leak. None of these will leave you stranded, but you'll fail emissions inspection and the cheap fix becomes expensive if you ignore it long enough. Get it scanned this week.
Get a free AI-ranked diagnosis for your exact year, make and model — with fair repair cost ranges and DIY-vs-shop guidance.