Lexus ES rough engine stalling

Sounds familiar. I had similar symptoms a while back: rough running, hesitation. It turned out to be an ignition coil issue. Have you checked the coil packs?

Ignition coil, huh? I haven't checked those specifically. Where are they located, and is there a way to tell if one is bad without special tools?

They're right on top of the engine, pretty easy to spot. You can try swapping them around to see if the misfire follows a specific coil. Honestly, the easiest way is to get a proper diagnostic scan done. Could be a bad cable or plug connection as well. That's what it was on my car.

Thanks for the tip! I took it to the shop, and you were spot on – it was a defective ignition coil and a bad connector. Cost me 95€ to fix, but it’s running smoothly now. Really appreciate the help!