Carl,
I did not notice any sparking in the car wheels.
I ran the Y3 with Legacy ON and the smoke unit OFF and had the same results, the cars were still flickering.
I did try the Y3 in conventional (with Legacy completely removed) and there was NO flickering. So it would seem that what ever the issue is it is related to the Legacy system. It is odd because I have used Legacy in the past with these same cars and never noticed an issue.
Now what is really odd, after about 30 minuets running with Legacy, and just dealing with the flickering passenger cars, it all stopped. Cars light up fine.
Thanks for the help all.
Ben