Engine light stays o n my 2006 impala

You may have to reset the engine light. These cars are all computerized. Call the dealership and tell them that you had to replace the gas cap as it was faulty and caused your check engine light to come on. Ask them if they can reset the "computer" or if they can tell you how to do it (if that is possible).

Don't know if that will work, but my dad has been in the car business for over 35 years - I tend to listen to most the things he says......

If I'm not mistaken if no other action is taken to turn the light off, there has to be so many start cycles before that history will clear. You could disconnect the battery for a minute or so and that would clear the history.Of course if the problem is still current the light will remain on.

After 3 warm-up cycles the check engine light will go out if it does not see a problem

Turn key to on position (not starting engine). Pump gas pedal three times. Start car. This resets computer and clears the code.