ski doo 800 e-tec engine problem...

I have a 2011 ski doo 800 e-tec with 481 miles on it. Dealer recall for new pistons etc. So I bring it to dealer he does recall. I have surgery done do not ride sled for two seasons....Then ride it this year  check engine light comes on after about five miles and it feels like it is flooding on low end but runs great on top end  mid range is a bit sluggish but not as sluggish and bottom end....Bring it to dealer he says that reed vales are not closing all the way and they are sticking ...I told him to fix it but then after a week he tells me it is getting several codes......in competent BS  I say......anyone have this problem ?  sled now has 509 miles on it...OH by the way when you turn sled off and restart it runs OK for about 5 minutes......  Would appreciate any help  now has been 11 days at dealer.......