And it's laggy when I driving fast through the city. I set my graphic settings to . YouTube™ Video: GTA IV Lag fix after 5 minutes. Views: 5, Well, after browsing the forum i managed to make a super-fast-amazing-comet- mod. I edited ledosynchging.ga file from \Grand Theft Auto. To enter cheats into Grand Theft Auto 4, you'll need to bring up Nico's phone and dial the corresponding phone number - or really, cheat code.