My 2002 Honda Odyssey has a problem with the heater. The air coming out is lukewarm at best sometimes it's cold. I feel the hoses to the heater and both are hot. Tried flushing out heater and the flow looks good. Don't know what's going on.
@speedcuber1
It is probably you need a whole new fan unit or something is wrong with your air condition when of the two things is wrong with it.
Check the coolant level too.
Seems to me that the heater core inside your dash is clogged up. If this is the case, it does not worth fixing. Use those electrical heater and/or electric cover seats.
There is a possibility that one of the blend door actuators is broken. There are several actuators that control doors under the dash... where the air blows and the temperature of the air. There are a few videos on YouTube, but not many that I could find for your era of Odyssey. Here's one that may help. https://www.youtube.com/watch?v=RNVieBwb3r4
