Sonata Hybrid engine stalling

Sounds familiar! I had a similar problem with my old Volvo. Check Engine light was the first sign, then it started stalling at stop lights. Turned out the hoses connected to the tank ventilation valve were completely clogged. Like trying to breathe through a pinched straw! It messed with the fuel/air mixture and threw everything off. Is it possible that your Sonata has a similar setup?

Interesting! Clogged hoses, huh? That's not something I would have immediately thought of. Where exactly are those hoses located? Are they easy to get to, or am I going to need to dismantle half the car to inspect them?

On my Volvo, they were a pain to get to – tucked away near the fuel tank. I ended up taking it to a shop because I didn't have the right tools to disconnect everything without damaging something. Honestly, given the symptoms and the mileage on your Sonata, it's probably worth having a professional take a look. It could be something else entirely, but if it is the ventilation, they'll be able to diagnose it quickly and clear those hoses (or replace them if needed).

Thanks so much for the advice! I took it to my local mechanic, and you nailed it! Turns out the tank ventilation valve hoses were indeed clogged. They cleared them out and replaced a slightly cracked hose, and the check engine light is gone, and it idles perfectly now! The whole repair cost me about 175€. Really appreciate the help!