Have 2011 gt500 with vmp tune and 2.59 pulley. While out for a run this morning engine light flashes for approx 30 sec then goes out. Checked for DTC codes. Found none,continued driving in spirited manner for an other hour.Engine light stayed off and no DTC code. Car performed flawlessly on whole trip.Outside air temp approx 30f,very cold here in New Zealand at the moment.Wondered if low temp leaned out a/f ratio.Thanks in advance for any suggestions.

That is indeed possible, and it has happened to me on very cold mornings when you first get into the boost. I also believe I read that the 2011's have a much more sensitivity to A/F due to the knock sensors and factory wideband? Somneone else may know better on that...

you more than likely pegged the maf due to cold air.