My heater blows, at most, slightly higher than ambient temperature. When I am at a stop, the heater gets slightly hotter. When I turn the setting to the coldest, it DOES get colder. AC works perfectly. I have already searched for the problem on the forum, but can’t find any related posts with a problem similar to mine. Just ones where the actual blower doesnt work or the temp doesnt change at all.

any ideas?

 

Sounds like the Air Mix Actuator may be malfunctioning. It blends heated and unheated air to produce the desired temp. The factory Body Electrical Troubleshooting Manual has diagnostic flowcharts with tests that might help ID the problem. See page G-21 in the 1994 version. Page G-33 shows the heater components. G-40 shows the Air Mix Actuator components.

http://www.wright-here.net/files/man..._tshooting.pdf

 

Are you low on coolant? The system requires a full radiator for the heat to work 100%.

 

rad is full

 

will check this out. Thanks!

 

https://www.rx7club.com/3rd-generati...ators-1066668/

 

I would also check to see that your heater core is not blocked. Run water through each of the opening to see if water goes out the other end.

 

Mine used to get barely warm, it was the thermostat, an unnamed shop drilled a hole instead of an OE with a jiggle pin, does NOT work the same. A brand new OEM tstat completely solved it. It was bypassing all the time, never stayed full temp so heat was ****. If yours stays at correct temp and doesn’t get warm I’d say your thermostat is fine, it’s something else only from my personal experience

 

Could also be that the actual door that moves to block and allow heat to come into the cabin May not be moving properly. Could be stuck or some of the connections loose or jammed if any debris got in there through the blower motor.

Absolute pain to take it all apart, but there is a great thread on here to fix and update the foam and connections in there.

https://www.rx7club.com/3rd-generati...hotos-1001759/

 

Things that usually cause that are:
clogged heater core
stuck thermostat
air in the cooling system
stuck blend door

From the symptoms you described, i'm betting on a clogged heater core or stuck thermostat. Check the thermostat first, then pull off the 2 lines for the heater core and try to flush it with brake cleaner and pressurized air. I've gotten lucky a couple of times and have flushed them enough that way. If you put it back together, bleed the system and it's not even slightly better, you would be looking at the blend door.

 

One more thing people sometimes don't realize and it just got me again today: heat DOES NOT come out of the face vents. Only floor and defrost.