Actual engine warms up however all the air from the ducts cold. As soon as I move in reverse or drive it heats up quickly is there a sensor possibly not working or maybe a thermostat starting to fail?

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https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-14.html#post2651405