DiRT 4 crash on startup Fix
Link to Patch - http://prey2017.pp.ua/?b=2&f=DiRT-4-Patch-Fix

1) Download the game patch
2) Run the patch installation
3) Start the game

Dirt 4 Game description:
Among other things, the tuning system will allow you to change the parameters depending on the machine, route and weather conditions. While specially hired engineers in the team's service area between the races will correct all your realistically reproduced damage (albeit for a limited time).