VW Sharan NOx Sensor Failure & Exhaust Leak Alert

As someone with some experience working on VWs, I dealt with a similar issue on my 2013 VW Touran TSI. The check engine light came on and I noticed issues with the exhaust system too. The workshop diagnosed a loose connection between the NOx sensor and its wiring harness. This was affecting the air-fuel ratio readings and triggering the pollution control system. Pretty common issue on these engines actually. Total repair cost was 95€, which covered cleaning the connections and securing the wiring properly. The fix took about an hour and solved both the check engine light and exhaust issues. No problems since then. Before giving more specific advice, could you share: Engine size and type, Current mileage, When did the symptoms first appear, Any other warning lights showing, Any performance changes noticed, Exact error codes shown These details would help determine if your issue matches what I experienced with the sensor connections. Worth checking all exhaust connections and mounting points first. Sometimes what seems like a complex sensor issue can be something as simple as a loose cable or connector.

As someone with some experience working on VWs, I dealt with a similar issue on my 2013 VW Touran TSI. The check engine light came on and I noticed issues with the exhaust system too. The workshop diagnosed a loose connection between the NOx sensor and its wiring harness. This was affecting the air-fuel ratio readings and triggering the pollution control system. Pretty common issue on these engines actually. Total repair cost was 95€, which covered cleaning the connections and securing the wiring properly. The fix took about an hour and solved both the check engine light and exhaust issues. No problems since then. Before giving more specific advice, could you share: Engine size and type, Current mileage, When did the symptoms first appear, Any other warning lights showing, Any performance changes noticed, Exact error codes shown These details would help determine if your issue matches what I experienced with the sensor connections. Worth checking all exhaust connections and mounting points first. Sometimes what seems like a complex sensor issue can be something as simple as a loose cable or connector.

As someone with some experience working on VWs, I dealt with a similar issue on my 2013 VW Touran TSI. The check engine light came on and I noticed issues with the exhaust system too. The workshop diagnosed a loose connection between the NOx sensor and its wiring harness. This was affecting the air-fuel ratio readings and triggering the pollution control system. Pretty common issue on these engines actually. Total repair cost was 95€, which covered cleaning the connections and securing the wiring properly. The fix took about an hour and solved both the check engine light and exhaust issues. No problems since then. Before giving more specific advice, could you share: Engine size and type, Current mileage, When did the symptoms first appear, Any other warning lights showing, Any performance changes noticed, Exact error codes shown These details would help determine if your issue matches what I experienced with the sensor connections. Worth checking all exhaust connections and mounting points first. Sometimes what seems like a complex sensor issue can be something as simple as a loose cable or connector.

Thanks for the advice. I have 85667km on the clock and just had the annual service last month. After reading your response, I checked the error codes again. The catalytic converter readings are also off, suggesting it might be more than just the nitrogen oxide sensor. The exhaust leak seems to be getting worse, especially during cold starts. The engine performance has dropped noticeably since these issues started. Taking it to a workshop next week, but wanted to get an idea if I should prepare for a major repair cost involving both the sensor and catalytic converter replacement. Looking at the symptoms you described, the wiring might be worth checking first before replacing any parts. Would you recommend having both components checked even if they find a loose connection?

Thanks for the advice. I have 85667km on the clock and just had the annual service last month. After reading your response, I checked the error codes again. The catalytic converter readings are also off, suggesting it might be more than just the nitrogen oxide sensor. The exhaust leak seems to be getting worse, especially during cold starts. The engine performance has dropped noticeably since these issues started. Taking it to a workshop next week, but wanted to get an idea if I should prepare for a major repair cost involving both the sensor and catalytic converter replacement. Looking at the symptoms you described, the wiring might be worth checking first before replacing any parts. Would you recommend having both components checked even if they find a loose connection?

Thanks for the advice. I have 85667km on the clock and just had the annual service last month. After reading your response, I checked the error codes again. The catalytic converter readings are also off, suggesting it might be more than just the nitrogen oxide sensor. The exhaust leak seems to be getting worse, especially during cold starts. The engine performance has dropped noticeably since these issues started. Taking it to a workshop next week, but wanted to get an idea if I should prepare for a major repair cost involving both the sensor and catalytic converter replacement. Looking at the symptoms you described, the wiring might be worth checking first before replacing any parts. Would you recommend having both components checked even if they find a loose connection?

Thanks for the additional details. Based on my Touran experience, the combination of catalytic converter readings and NOx sensor issues often points to a broader exhaust system problem. When my workshop did the initial wiring fix, they actually discovered hairline cracks in the catalytic converter housing. These tiny cracks were causing both the sensor misreadings and the exhaust leaks, especially noticeable during cold starts just like yours. The full repair ended up including: Wiring harness inspection and repair: 95€, Catalytic converter replacement: 780€, New emission sensor set: 320€ The performance drop you mentioned matches what I experienced. The diesel engine was struggling because the pollution control system was getting incorrect readings, causing it to run rich to compensate. Definitely have them check both components. In my case, just fixing the wiring would have been a temporary solution. The workshop should perform: 1. Complete diagnostic scan 2. Visual inspection of the entire exhaust system 3. Check all sensor connections 4. Test catalytic converter efficiency The check engine light issues with these models often involve multiple related components in the emission system. Better to catch all problems during one repair session than face repeated workshop visits.

Thanks for the additional details. Based on my Touran experience, the combination of catalytic converter readings and NOx sensor issues often points to a broader exhaust system problem. When my workshop did the initial wiring fix, they actually discovered hairline cracks in the catalytic converter housing. These tiny cracks were causing both the sensor misreadings and the exhaust leaks, especially noticeable during cold starts just like yours. The full repair ended up including: Wiring harness inspection and repair: 95€, Catalytic converter replacement: 780€, New emission sensor set: 320€ The performance drop you mentioned matches what I experienced. The diesel engine was struggling because the pollution control system was getting incorrect readings, causing it to run rich to compensate. Definitely have them check both components. In my case, just fixing the wiring would have been a temporary solution. The workshop should perform: 1. Complete diagnostic scan 2. Visual inspection of the entire exhaust system 3. Check all sensor connections 4. Test catalytic converter efficiency The check engine light issues with these models often involve multiple related components in the emission system. Better to catch all problems during one repair session than face repeated workshop visits.

Thanks for the additional details. Based on my Touran experience, the combination of catalytic converter readings and NOx sensor issues often points to a broader exhaust system problem. When my workshop did the initial wiring fix, they actually discovered hairline cracks in the catalytic converter housing. These tiny cracks were causing both the sensor misreadings and the exhaust leaks, especially noticeable during cold starts just like yours. The full repair ended up including: Wiring harness inspection and repair: 95€, Catalytic converter replacement: 780€, New emission sensor set: 320€ The performance drop you mentioned matches what I experienced. The diesel engine was struggling because the pollution control system was getting incorrect readings, causing it to run rich to compensate. Definitely have them check both components. In my case, just fixing the wiring would have been a temporary solution. The workshop should perform: 1. Complete diagnostic scan 2. Visual inspection of the entire exhaust system 3. Check all sensor connections 4. Test catalytic converter efficiency The check engine light issues with these models often involve multiple related components in the emission system. Better to catch all problems during one repair session than face repeated workshop visits.

Thanks for sharing those details. The exhaust and performance symptoms do sound concerning. After digging deeper into my situation, I see the emission sensor and catalytic converter problems are likely connected. I will definitely ask the workshop to do a thorough inspection of both components next week. Your breakdown of the potential repair costs helps set realistic expectations, good to know I might need to budget around 1200€ if both parts need replacing. The air-fuel ratio being affected makes sense given how the engine is performing. I will have them start with checking all connections and wiring before moving to component replacement. The check engine light staying on and worsening exhaust leak suggest this needs proper attention soon. Will update once I get the workshop diagnosis. Hopefully they can identify if mine has similar catalytic converter damage or if its just sensor and wiring related. Really appreciate the detailed repair cost breakdown and inspection recommendations.

Thanks for sharing those details. The exhaust and performance symptoms do sound concerning. After digging deeper into my situation, I see the emission sensor and catalytic converter problems are likely connected. I will definitely ask the workshop to do a thorough inspection of both components next week. Your breakdown of the potential repair costs helps set realistic expectations, good to know I might need to budget around 1200€ if both parts need replacing. The air-fuel ratio being affected makes sense given how the engine is performing. I will have them start with checking all connections and wiring before moving to component replacement. The check engine light staying on and worsening exhaust leak suggest this needs proper attention soon. Will update once I get the workshop diagnosis. Hopefully they can identify if mine has similar catalytic converter damage or if its just sensor and wiring related. Really appreciate the detailed repair cost breakdown and inspection recommendations.

Thanks for sharing those details. The exhaust and performance symptoms do sound concerning. After digging deeper into my situation, I see the emission sensor and catalytic converter problems are likely connected. I will definitely ask the workshop to do a thorough inspection of both components next week. Your breakdown of the potential repair costs helps set realistic expectations, good to know I might need to budget around 1200€ if both parts need replacing. The air-fuel ratio being affected makes sense given how the engine is performing. I will have them start with checking all connections and wiring before moving to component replacement. The check engine light staying on and worsening exhaust leak suggest this needs proper attention soon. Will update once I get the workshop diagnosis. Hopefully they can identify if mine has similar catalytic converter damage or if its just sensor and wiring related. Really appreciate the detailed repair cost breakdown and inspection recommendations.