loud or rough idle when cold

[ivanhoe67]

I just bought a 2015 Mazda 3 itouring, 2.0 liter, auto. Our test drive was in the afternoon, car ran great. The next morning when it was cold, the car idle sounded a bit rough and loud. After 2 minutes it smoothed out. Is this normal? I called the dealership and they said yes. There is the "blue" light for engine temp that lights up and goes out. Just wondering if anyone else has experienced this.

Thanks

 

[ceric]

Yes.
Initial high RPM idle is to heat up the CAT quickly to comply with emission regulation.

 

[larson701]

And yes, the sound of the engine is louder and rougher too. Believe the explanation is in the manual.