Started my car for the first time in about 2 weeks tonight. Pretty cold out, so we turned on the heat. The problem is, now the temperature control no longer does anything. No matter what, it is just really hot air. Running the A/C cools it down a good bit, but not what it should. It was roughly 40 degrees out, so it just isn't warm outside air.

It's a '95 if it matters much.

Anyone got any ideas?

Thanks a lot

 

I had the same problem on my old Silvia (CA18DET (240sx), but I did find the cause (discovered after many hours of wire testing, and rummaging under the dashboard)

The in-cabin temperature sensor was broken, giving the A/C controls a false value of COLD. No matter what mode the controls were in, it would always try to heat the car.

I replaced the sensor, and it fixed the problem. Hope the RX7 is the same!