2020 Kia Stinger — a/C is cold on the highway but warm at stoplights — second opinion before I spend money

I'd want a measurement, not a hunch. Move a coil or plug on the 2020 Kia Stinger if it's cylinder-specific and see whether the code follows. If the cheap test changes it, stop and reassess. Write the result down so the next test isn't a repeat of the last one. I'd sleep better after that step, even if it finds nothing. I keep a notes app thread for this now.

If it were in my driveway, swap the cheap/easy piece first on the 2020 Kia Stinger and see if the fault moves. If the cheap test changes it, stop and reassess. Learned this the expensive way on a previous car. I'm keeping receipts and dates in one folder.

This is usually cheaper to test than to guess. Capture voltage while the 2020 Kia Stinger is actually failing — after it restarts you've lost the clue. Don't erase codes until someone who can help has seen them. I'd want that in writing, not as a promise. I keep a notes app thread for this now.

Ask what changed right before it started. Write temp, speed, and in-gear vs coast when the 2020 Kia Stinger does it — then decide on parts. Don't erase codes until someone who can help has seen them. Learned this the expensive way on a previous car. That's coming from doing this as an owner, not a shop. Happens in gear, not in park, for what that's worth.

Intermittent stuff lies if you only catch it once. Capture voltage while the 2020 Kia Stinger is actually failing — after it restarts you've lost the clue. If the cheap test changes it, stop and reassess. On “a/c is cold on the highway but,” that was the fork that mattered for me. That's the whole play. Not interested in a five-hour wait for a shrug.

I wouldn't throw parts yet. Get a real battery/charging test on the 2020 Kia Stinger, not just resting voltage, before blaming a module. You'll know quickly if you're on the wrong tree. That's the whole play. I'll poke at it this weekend.