Engine Noise while Idle

[colinchrisc]

So I just got my 2010 Mazda 3 and it's great, however, I've been hearing a quick engine growl after starting the car while waiting for it to warm up. The noise happens about once every 20 seconds and is a quick growl as if i were to quickly push on the gas in neutral. I'm assuming this is normal but should I be worried? Could it be the alternator? Battery?

Thanks in advance.

[Zoom Zoom Boy]

So I just got my 2010 Mazda 3 and it's great, however, I've been hearing a quick engine growl after starting the car while waiting for it to warm up. The noise happens about once every 20 seconds and is a quick growl as if i were to quickly push on the gas in neutral. I'm assuming this is normal but should I be worried? Could it be the alternator? Battery?

Thanks in advance.

Are your air vent settings set to the window or window/floor setting? If so, this activates your AC compressor to remove moisture from the car to help defrost and clear up your windows. Again, assuming that is the case, you are likely hearing the AC compressor cycle on and off. The noise in this case, is entirely normal.