Posted this in the Tech Q&A, too, putting it here, too, since there are more owners frequenting. My Cali T runs fine, no check engine lights, pulls hard. However, it's always had an intermittent noise in the exhaust at idle, most prominently when the AC is off and the idle is a little lower, although it will do it with the AC on, too. Hard to describe, you feel a little shake in the cabin, although the RPMs do not fluctuate on the tach. I recorded a quick video by the tailpipe, sounds like a knocking or a popping sound. Does it at 4 seconds, 7 seconds and 21 seconds. Mostly I notice this idling at stoplights. This is with the car up to temperature, after a 30 minute drive. Not sure how normal this is or if it's perhaps the motor mounts or ... maybe it's nothing. I will be taking it for service in the next few weeks, but curious if anyone else has experienced. Car has about 15k miles and is under the New Power warranty.