Can you please let me know a few things.
1) How old is your yorkie?
Tucker turned 1 at the end of september
2) How much does he/she weigh?
9/10 pounds
3) How long can he/she hold their pee?
During the day he does out about every 2 hours, pees everytime. We take him out for his last pee before bed anywhere between 9/10pm and he needs to go asap by 6/630 am or he will pee in his kennel. I still have to be very consistant and watch him all the time during the day because if I dont see him pacing/sitting most of the time by the door, (but not always) he will have an accident. If hes got go, hes got a go, there is no holding it.. 
... (he reminds me of that tv commercial, got go, got go right now..lol) My toy poodle on the other hand is between 4/5 pounds will hold it for hours and most of the time I make her go out.