I don't have any hot air coming from the vents. I tried this method https://www.rx8club.com/showthread.p...heater&page=13 but the thermostat works just fine. What would be the problem? Stuck open thermostat? Clogged heater core? How do you figure out what the problem is and what would the solution be?

 

Congratulations ....

https://www.rx8club.com/series-i-do-yourself-forum-73/what-belongs-diy-forum-163653/

 

A quick search will show that this is an incredibly common issue for RX-8s, and has to do with the temperature control **** joint.

 

Please read my original post here:
I don't have any hot air coming from the vents. I tried this method https://www.rx8club.com/showthread.ph...heater&page=13 but the thermostat works just fine. What would be the problem? Stuck open thermostat? Clogged heater core? How do you figure out what the problem is and what would the solution be?

thermostat works just fine, by this i mean the temperature control ****, also known as a thermostat in HVAC terms.

 

oops didn't know that!!

 

I bolded the part where you may wish to be more clear in the future. I DID read your original post, the part where you didn't refer to the temperature control ****, but instead referred to a completely different and unrelated part. There is an actual part which is named the "thermostat", and it controls the flow of coolant around the engine/radiator. Referring to something other than the thermostat as "the thermostat" is going to create just as much confusion as if you say "when I turn on my blinker, I can't see as far down the road, and by blinker I mean high beams". Yes, I understand you are probably more familiar with using HVAC terms, but coming to a car forum, people from whom you are requesting help aren't expecting anything but car terms.

Your link isn't valid, but I am going to assume you linked the temperature control **** repair thread.

Heater core is the only other option I think.

Can you create cold air? (may help narrow the possibilities)

 

Could it be a stuck mixer/blend door actuator?

 

I'm not exactly sure if I'm right, but I think I have this same problem, only instead of no heat, i get no cold air. its a flap or door that flips between heater core and ac. try moving the temp **** all the way cold for 10 seconds, then move it back to heat. sometimes it will flip the door back open. also dont run the fan on high or 4, run it on lower settings so it wont put extra pressure on the door. I think its just a simple fix, I believe the person referring to "actuator" is correct, I keep calling it a door, but in simple terms its a door that flips between hot and cold air.

 

It gets hot now. I am not sure what the problem was. The "door" would work, or sound like it worked. When I switched it over without my 8 started you could hear it doing something when you changed temperature.