Weird interior heating/cooling issues

Oct 3, 2022
Hey everyone,

I have a Leon Cupra MY 19 with some pretty weird interior heating/cooling issues - or at least I think they're issues. During summer when the temperature is around 30C outside and the car is sitting in the sun for most of the day, I air it out and switch on the A/C. Now I know it's hot in the cabin, but I've never had to set the temperature to 24, 25C or more because the car blows freezing cold air. In all of my other cars, I set the temperature around 22C and it would be just right.

Now the heating problems is the other way around. In the morning when the outside temp is around 10C, I set the interior to 23C and it immediately starts blowing very hot air. After 10-15 mins, the air suddenly becomes cold and I need to raise the temperature if I want heat. The repair shop hasn't found anything, but I think they only checked for faults.

Thanks in advance!
Mar 8, 2024
Hello abazigal, I don't know if you solved your problem.
I have a 2019 Seat Leon Cupra 2.0 TSI 290 and I've the same problem. I have to set to 27°C to be "good" in the cabin. When the car is started, the first 5 minutes I can get hot air at 22/23°C. But after 5 mins it's getting cold and then very cold..

I hope you solved it and you may add a comment to help me to find a solution to this because the dealership told me the same thing : they didn't find any issue about cabin heating..

Greetings from France,



Active Member
Jul 14, 2017
Hey Guys, am not a mechanic, but.....
*It could be low on coolant, even when the overflow looks full, still check if the radiator is full as well.
*thermostat could be broken/not opening fully or not at all.
*air locked, seemingly you can unlock the heater matrix to let air out.
*restricted flow of the coolant, dirt in the hoses or a kinked hose.

personally, I think the thermostat is gone,(hopefully) its a quick fix....

Good luck.
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