iRacing 2025 S3 Patch 4 hotfix updates Moza stability and Dallara IR18 displays
This hotfix addresses a critical Moza API crash issue in long sessions and adjusts the Dallara IR18 pit limiter light and digital display.
We’ve got a small iRacing hotfix update here, focused on critical fixes for the 2025 Season 3 release. The official notes are in the hotfix release notes.
What changed
Features
- Release notes for 2025 Season 3 Patch 4 Hotfix 1 [2025.08.06.02].
Fixes
- iRacing says this hotfix contains critical fixes for issues introduced with the 2025 Season 3 release.
- In Simulation > Controls, a critical issue with the Moza API was fixed that could cause the simulator to crash after running for nearly 3 hours.
Cars
- Dallara IR18
- Improved the pit limiter light implementation.
- MPG has been added back to the digital display.
For league ops, we should retest endurance-length sessions on Moza-equipped driver stations and let IR18 drivers know the in-car display and pit limiter indicators have changed.
From the changelog
Structured change list parsed from the official notes.
features
- [h2] 2025 Season 3 Patch 4 Hotfix 1 Release Notes \[2025.08.06.02] [/h2]
fixes
- This Hotfix Release contains critical fixes for issues with the 2025 Season 3 Release.
- [h2] SIMULATION: [/h2] -------------------------------------------------------------- [h3] Controls [/h3] [*] Fixed a critical issue with the Moza API that was causing the Simulator to crash after running for nearly 3 hours. [/*]
cars
- [h2] CARS: [/h2] -------------------------------------------------------------- [h3] Dallara IR18 [/h3] [*] Improved the pit limiter light implementation. [/*][*] MPG has been added back onto the digital display. [/*]
Official sources
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