Thanks again for responding. I wish you guys worked at the repair shop I go to! 
Iāve made some notes and will take my trailblazer back and suggest they check those things you mentioned. I just canāt say it enough - I love this website and appreciate the input I get. Thanks!!
Go to the link below, read the original post, then jump to the post by tblazed. (You must become a member of TrailVoy to read the how-to article, but the lowest level of membership is free.)
I found the post. Wow. Exactly what my vehicle is doing. You guys ROCK! Thanks!
Hopefully that will be your problem. Good luck and let us know.
Update: Dirty Throttle Body. Something about it being 14 degrees(?) offā¦ $59 to clean. Woo hoo!