What is a engine code P0172

Try Googling it. There's a ton of information there that will help you.

Thank you, it was a vacuum leak that was causing smoke to come thru the vents, after bleeding the air from the line(heater core) (its running fine (so far) no problems:) Thankx for the help I got the car@auction 4a great price knowing it needed work, this site has been awesome! I now have a car:) I'm disabled & been without for almost 2 years! I had the heater chore, teasinor& water pump changed ! Thank you thank you thank you, I couldn't of done it without this site & the help given, Thankx again Leslie

Your welcome. Glad you got it going. Drive safe.