Lerching and engine dies down

I have a 1991 Mazda B2200 stick shift which has 110,000 miles on it. My problem is in the last two winters the car lerches and the engine dies down when I start it and comes to stop sign. It’s worse during the winter time. Now starting last week I noticed the problem too. Is it a carburator issue or something else? My mechanic suggested to change the carburator. I have done tune up last year. I need your help desperately.

Kebena from KS