After several fans reported that they were experiencing issues with modifying a vehicle on the Xbox One and Playstation 4 editions of Grand Theft Auto V, Rockstar Games acknowledged that a bug was known to be currently affecting several players who have modified vehicle tuning. The developer revealed that they are aware of the issue within GTA V and are currently investigating it in order to find a solution.
The bug is forcing cars that have been upgraded with turbo tuning to actually go slower than those with unmodified tuning. Since the point of paying for turbo tuning in GTA V is to make any given car faster, many users are frustrated that the issue is causing the mod to have the opposite effect.
The issue only seems to be affecting the Xbox One and Playstation 4 versions of GTA V at this time so gamers on last-gen consoles don’t need to worry about the bug.