Flashing CEL and Rough VW Taigo Needs Urgent Fix

I experienced similar symptoms on my 2019 VW T-Cross with the 1.0 TSI engine. The rough running and exhaust smell turned out to be a combination of issues, a cracked exhaust pipe near the manifold and a failing Lambda sensor. The exhaust leak was causing incorrect readings in the engine management system, which then affected the fuel mixture. This created a cycle where the engine ran increasingly rough. The check engine light started flashing because the system detected potential catalytic converter damage due to the improper fuel mixture. The repair required replacing both the damaged section of the exhaust pipe and the Lambda sensor. The job needed specialized diagnostic equipment to properly calibrate the new sensor. This was definitely a serious issue that required immediate attention, as continuing to drive risked damaging the catalytic converter and creating unsafe conditions with exhaust fumes. Given your symptoms, especially the visible exhaust leak, I suggest having it checked at a certified VW workshop where they have the proper diagnostic tools. With exhaust system issues, its crucial to get an accurate diagnosis since multiple components can trigger similar symptoms.

Really appreciate your detailed response on the exhaust leak situation. My car ended up having similar issues, the exhaust pipe was damaged and there were also problems with the NOx sensors. The malfunction definitely caused the engine to run poorly. I ended up taking it to a certified shop since I wanted to make sure they could properly diagnose and fix all the exhaust system components. They also checked the particulate filter while they were at it. Would you mind sharing how much you paid for your repair? Just wondering how the costs compare. Also curious if you had any other issues pop up since getting it fixed?

Thanks for the update on your repair. Since getting my VW fixed, the exhaust treatment malfunction warning completely disappeared and the engine has been running smoothly. The total repair cost was 375€ for replacing the defective Lambda sensor, which was a fair price considering the specialized diagnostic work needed. The engine light never came back on and the exhaust system has been working perfectly. They did a thorough check of the EGR valve and NOx sensors during the repair to ensure there were no other developing issues. Really glad I got it handled at a certified shop, their diagnostic equipment caught everything the first time. The original exhaust pipe repair and sensor replacement took care of all the symptoms completely. No more rough running or exhaust smells. Going to a qualified shop might cost a bit more upfront, but getting it done right prevented any repeat problems or additional repairs later.

I took your advice and got everything checked at the certified VW workshop. The total repair came to 890€, more than I hoped but worth it to fix it properly. They replaced the cracked exhaust pipe section and both faulty NOx sensors that were causing the malfunction. The catalytic converter showed early signs of damage from the exhaust leak but luckily they caught it in time. The engine light went off right after the repair and the car runs perfectly smooth now. No more rough idle or exhaust smell issues. The certified techs definitely knew what they were doing. Their diagnostic equipment picked up problems my previous mechanic missed completely. Seeing how complex these exhaust systems are, I understand why the generic shop couldn't properly diagnose it. Next time I notice any engine light or exhaust issues, I'm going straight to the dealer.