check engine warning light just appeared.

You won't see the problem because it's probably electrical. Take it to a Hyundai or Mitsubishi specialist for diagnosis and estimate. The check engine light indicates that the computer has detected a malfunction in the engine/transmission control system and has diagnostic codes and data stored which would be essential in diagnosing the problem. A technician with a scanner can access the diagnostic codes and data and then be able to give you a diagnosis. If you want to find a specialist, here's our directory link for you: https://repairpal.com/hyundai-repair-in-hadley-new-york

Something as simple as not screwing the gas cap correctly can cause this.