Starting issues

I've seen threads about this before on here, however after searching i couldn't find them again, so i apologize for the repeat.
When my truck sits for a while whether it really cold or hot out, when i turn the key it starts right up with no hesitation. Which i am really impressed with even in this cold weather. However, if let it sit for a little while, like when im in class. When i go to start it, the truck hesitates and takes a few cranks. It turns over, but barely and the rpm's are low. They eventually rise and everything is normal.
I think i remember reading that there was a tsb on one of the wire harnesses, or the O2 sensor, but i can't remember for sure. Any ideas?

 

any idea on what they might cost me to have replaced since its well out of the warranty period?

 

damn, did it get any worse with time or did you fix it right away?

 

Thanks for the help, i found a full detail pdf file on custom tacos about redoing the harness. However i cant find a price for parts for either, i'm gonna check out liberty toyotas to see if they can give me an estimate.