The problem was that the car started perfectly cold, but as it warmed up, the engine began to work very unstable, producing gray smoke and could even stall. After stalling, it became hard to start again, and cranked poorly, like a dead battery. I thought long about where to look, built the worst scenarios but decided to start with the cheapest solution, changing the temperature sensor that goes to the engine management system with two contacts; at the same time, I went in there and bought a thermostat and temperature gauge.

To my surprise, after replacing the faulty temperature sensor all symptoms disappeared. Plus, the car warms up faster now, no thermostat was even installed! It's good I decided to open it up.

No photos, nothing special to photograph, unscrew the old one, screw in the new one))