RSQ3 Power Loss: Common Causes and Real Solutions

I had a very similar issue with my SQ3 from 2019 which sounds exactly like what youre experiencing. I have some experience working on cars and doing basic maintenance, but this was definitely beyond my skill level. The reduced power mode and multiple fault codes pointed to chip tuning problems. A proper car diagnostic revealed that a third-party tuning modification was causing conflicts with the engine management system. The check engine light kept coming on, and the performance was terrible. I took it to a specialized workshop that deals with engine management systems. They had to reset the ECU to factory settings and properly reinstall the original programming. The total repair cost was 180 Euro, but it completely resolved the issue. No more error codes since then, and the engine performance returned to normal. Before suggesting more specific solutions, could you share: What year is your RSQ3? When did the problem first start? Have you had any recent modifications or tuning done? Which specific fault codes is your scan tool showing? These details would help determine if youre dealing with the same root cause I encountered.

80682 KM on the clock. The car computer initially showed just one fault code, but now multiple codes appear. Taking it to my regular service center next week. They did a software update during the last maintenance about 2 months ago, which might be related to the current engine issue. The auto scanner shows P0299 among other codes, suggesting possible turbo underboost problems. No aftermarket modifications have been done to the car. All maintenance has been performed according to schedule with genuine parts only.

Based on your description and the P0299 code your diagnostic scan revealed, this sounds very similar to what I experienced after my service center performed a software update. The turbo underboost issue combined with multiple fault codes matches the pattern I saw. In my case, the software update had some compatibility issues with the engine management system. The check engine light kept triggering and the car went into reduced power mode as a safety measure. While P0299 typically suggests a mechanical turbo problem, in our specific engine configuration it was actually related to the ECU programming. Have the scan tool check all sensors connected to the turbocharger system. My repair required: 1. Complete system diagnostic scan 2. ECU software rollback 3. Fresh installation of the correct software version 4. Clearing all stored fault codes 5. Verification test drive Total repair cost was around 250 Euro in my case. Make sure your service center is aware of the timing between their software update and these issues appearing. They should be able to verify if theres a known compatibility problem with that specific update on our engine type. Would recommend having them focus on the software angle before exploring mechanical turbo issues, since the timing with the recent update is quite suspicious.

The check engine light came on today again. Had a full vehicle diagnostics test run which showed even more fault codes than before. I can confirm the software update timing lines up perfectly with when these issues started appearing. After reading about the similar experiences here, I will specifically ask the service center to investigate the software angle first. No point replacing expensive turbo components if its just a programming issue. Will make sure they follow the repair steps suggested, especially checking the ECU programming and software compatibility. Thanks for sharing the detailed repair process and costs. Having this information helps me go into the service appointment better prepared. Will update once they complete the diagnostics and fix the root cause of these fault codes.