I just recently replaced my timing belt, serpentine belt and spark plugs on my IS with 124.000 miles on it. The car running great and a couple of days ago my check engine light kicked on with my VSC and traction control lights. I had the codes ran which brought up P0442 twice and P0446. Anything would be helpful.

Those codes usually come from the gas cap not being on tight enouph, or needing to replace the gas cap, or if the VSV valve isn't connected to the vacuume tube off the gas tank. It's right next to the air intake box. IF you just had a bunch of work done, I would bet that's the problem. Probably forgot to reconnect it.