The “invalid car heat value” error — causes and diagnosis

: Locate your save at Documents\NFS Carbon and copy the folder starting with your alias name (e.g., A[YOURNAME] ) to a safe location.

: A frequent side effect of editing these values is the "no car in garage" issue, where your vehicles disappear from your career safehouse.

: Many save editors fail to apply changes correctly if they lack administrative permissions to write to the Windows Registry. Disable Real-Time Protection

Remember: In NFS Carbon, exclusivity means immunity. If you want heat, you have to give up the "Exclusive" badge.