Just car the back; no difference... errrggghhhh... It's going back Monday anyway because they didn't get the wire set on. That could the vibration at idle problem, but I would expect more dramatic problems.
The cap & rotors were replaced at the 90k service.
I think the crank sensor only plays a part during engine set-up, not sure though. It determines the position of the crank shaft; I've read about in one of the other posts here. I'll try starting it a couple different times after varying time intervals and see if the cold start issue is gone.