Thermostat not registering

[Bacon]

On my gauge cluster, my thermostat will read a temperature when I am sitting still idling but then it drops back to full cold when I start moving again. Heat works great and is not affected. Would it be my temp sensor?

[D3UC3S]

yeah the contactor is probably worn out or the wire is loose. If that doesnt fix it, check the tension on the alternator belt. Mine would go up with the rpms and it ended up being a loose belt. It freaked me out but it took 2 seconds to fix.

[Bacon]

Okay cool. I will check those two. Any other input is appreciated.