S8 Power Loss Due to Exhaust Temp Sensor Malfunction

Having experienced similar issues with my A6 3.0T from 2013, can confirm these symptoms align with a faulty exhaust temperature sensor. The check engine light and power reduction are typical warning signs when the engine management system detects sensor malfunction. During my repair, the diagnostic revealed the temperature sensor was sending incorrect readings, causing the engine to run rich. This led to increased fuel consumption and the power reduction you described. The sensor replacement itself was straightforward, but accessing it required partial removal of the exhaust system components. In my case, the issue was serious enough to require immediate attention since prolonged operation could damage the catalytic converter. The repair involved: Full diagnostic scan, Exhaust temperature sensor replacement, Engine management system reset, Test drive to confirm proper operation Getting a second opinion is always wise for exhaust system repairs, especially given the complexity of modern engine management systems. Look for shops specializing in Audi/VW diagnostics, as they will have the proper diagnostic equipment for these specific sensor issues. The repair restored normal power delivery and fuel consumption returned to standard levels. Consider this a priority repair to prevent potential damage to other exhaust components.

Thanks for sharing that experience. Mine showed the exact same symptoms with the temperature sensor and power reduction. Mechanic did everything you mentioned, and the car runs perfectly now, back to normal power and fuel economy. Just wondering though, what was your total repair cost? Curious if it matches what I paid. Also, have you noticed any other temperature fluctuation issues or sensor problems since the fix? My A8 had no issues after the sensor replacement, but its always good to know what to watch for with these exhaust component repairs.

Good news on getting the exhaust temperature sensor fixed. My total repair cost was 265 Euro, which covered fixing a small leak they found in the exhaust system while replacing the sensor. The temperature sensor replacement has been completely reliable since the repair, no more check engine lights or power issues for over 18 months now. The exhaust system has been working perfectly with stable readings from all sensors. A quality repair should fully resolve these temperature sensor problems without any recurring issues. Just keep an eye on your fuel consumption patterns, any sudden changes could indicate other sensors need attention, but this is rare after a proper fix. The key was having a qualified shop that properly diagnosed the faulty sensor and checked the surrounding exhaust components while doing the work. Proper diagnostic equipment makes a big difference with these sensor-related repairs.

I finally got my car fixed last week and wanted to update everyone. Found a great mechanic who specializes in VW/Audi, total repair cost was 320 Euro for the complete exhaust sensor replacement and diagnostic work. The repair took about 3 hours. They confirmed the faulty exhaust temperature sensor was causing the power loss and high fuel consumption. The mechanic showed me the old sensor and explained how it was sending wrong readings to the emission control system. After the fix, the car runs like new again. Fuel economy is back to normal and full power is restored. No more check engine light either. The shop also did a full system scan to make sure no other exhaust components were affected. Really glad I got this done, the exhaust sensor issue could have caused more expensive problems if left unfixed. Thanks everyone for the advice on getting it properly diagnosed and repaired.