I haven’t played GTA IV since 2020 then I came across a YouTube video by TJGM about an open source GTA IV mod called Fusion Fix, which essentially fixes issues that exist in the game that were left unaddressed & includes graphical features. The project was created by ThirteenAG (https://github.com/ThirteenAG)

Works only for: Grand Theft Auto IV: The Complete Edition

Version 5.0.0 of Fusion Fix dropped recently and was a big update, so I decided to try it out myself. It includes many fixes such as fixing console gamma so it now applies across the whole UI, restoring death music, plus introducing ambient occlusion in the graphics menu. Given that the project is open source, Fusion Fix can be maintained and updated by the community for a very long time.

Installation is very simple; you just download a zip file from their GitHub page & extract the contents in the same directory as the game’s exe file, that’s it.

Website: https://fusionfix.io/iv

GitHub repository: https://github.com/ThirteenAG/GTAIV.EFLC.FusionFix