Chevrolet Optra Problem

I'd been having problems with my Chevrolet Optra, it suddenly turns off when i'm running or parked

Hi Scotty! Big fan from Costa Rica desperately looking for answers, I have a Chevrolet Optra 1.6, it runs ok, but sometimes ( like every 2 days ) suddenly the engine turns off so, when i turn it back on (running or parked) it starts like losing power and you can smell the gas bad burned or something, and if i don't keep my foot on the gas pedal it turns off again, so i have to keep it accelerated to continue running , it doesn't keep the minimum RPM, i already changed coils like 2 years ago, sensors, throttle body, i think everything LOL, but i need your expertise here, i recently changed the fuel filter and it improves a lot , i mean 5 days in a row without a problem instead of the once daily i used to, but today the same happens to me again, need some ideas where to start checking again buddy! Thanks for your help Scotty, i really appreciate it.

try having the fuel injectors pressure cleaned, leaking injectors often do that. Also have the maf sensor checked, they can be cleaned as in this video https://www.youtube.com/watch?v=NWCKvU2FmDc