Audi TT Engine Power Loss: Warning Signs & Solutions

I had a very similar issue with my 2021 Audi RS3. Having some experience with engine management issues, I can share what worked in my case. The reduced power and engine fault were also present in my car after getting a third-party chip tune. The car computer was showing multiple fault codes, which initially made diagnosis tricky. Using a car diagnostic tool revealed conflicts between the custom tune and the factory ECU settings. The workshop connected their professional vehicle diagnostics system and found the tune was causing conflicts with various engine management parameters. They had to: 1. Reset the ECU to factory settings 2. Clear all stored fault codes 3. Run a complete system diagnostic 4. Perform several test drives to ensure normal operation The total repair cost was 180 Euro and completely resolved the performance issues. The car went back to running at full power with no warning lights on the dashboard. Before suggesting specific solutions for your TT, it would help to know: Did you recently get any performance modifications? Are there any dashboard lights currently on? What exact symptoms do you notice during driving? Have you already used an auto scanner to check for codes?

Last service was at 50000 km, and my dashboard light just started showing last week. After trying the suggestions in the previous reply, still experiencing the same reduced power symptoms. My scan tool displays error P0299, pointing to a turbocharger underboost condition. The car computer seems to be limiting power output as a protective measure. Would getting the turbo checked be the next logical step? The engine issue persists even after clearing the codes.

Thanks for providing that additional detail about error code P0299. Having gone through turbo-related issues with my RS3, this fault code definitely warrants attention. After my ECU reset experience mentioned before, I actually encountered this exact turbocharger underboost condition. The car diagnostic system showed P0299 just like yours. When the check engine light appeared with reduced power, it turned out to be a boost leak from a cracked intercooler pipe. Common causes for P0299 in our engines typically include: Boost leaks from loose or damaged hoses, Clogged air filter, Faulty wastegate actuator, Malfunctioning turbo, Blocked catalytic converter Since clearing the fault code didnt solve the issue, a proper inspection of the turbo system components is definitely the next step. In my case, the auto scanner helped identify the general area, but finding the actual boost leak required a pressure test. Consider getting a boost leak test done before assuming the turbo itself is failing. My repair involved replacing the intercooler pipe and cost 320 Euro, which was much better than a full turbo replacement. Have you noticed any unusual sounds like hissing under acceleration? This could help pinpoint if its a boost leak rather than a turbo issue.

Thanks for the thorough response regarding the P0299 code. After hearing about your experience, I checked for boost leaks today and discovered a small crack in one of the intercooler pipes, exactly as you described. This explains the engine issue and reduced power symptoms perfectly. I can even hear a subtle hissing sound during acceleration that I hadn't noticed before. The vehicle diagnostics from my scan tool make much more sense now. Going to schedule a repair to replace the damaged pipe rather than jumping straight to turbo concerns. Good thing I didnt rush into more extensive repairs. The check engine light issue seems directly related to this boost leak. Really appreciate the detailed breakdown of potential causes, saved me from potentially unnecessary turbo work. Will update once the intercooler pipe is replaced to confirm if this resolves the performance limitation.