chimchamp

ANy clues here? It just started (150k miles) I've had it for a week.... it worked somewhat normally, but was a little inaccurate when you adjusted temp.... now it's just full hot all the time, the dial won't mix in cool air.... it's a servo motor flap deal? Where is the item, how hard to swap, how much is the part?

Thanks,
Mason

P.s.

Full cold doesn't mix in cold air, so I assume it's not temp sensor related.