VW Sharan Diesel Moisture Sensor Causing Engine Issues

Had the same sensor issue on a 2012 VW Touran 2.0 TDI. The rough running and check engine light matched your symptoms exactly. The water sensor fault triggered similar error codes. The root cause was a deteriorated wiring harness connecting to the water-in-fuel sensor. Moisture had corroded the connector pins and created an intermittent electrical fault. While the sensor itself was functional, the damaged wiring connection caused false readings. The repair required replacing the complete sensor wiring harness and connector assembly. This was not a quick fix as accessing the sensor connection point needed partial removal of the fuel filter housing. The electrical fault symptoms completely resolved after the repair. This is a known weak point in these engines. Would suggest having a specialist shop handle it since proper waterproofing of the new connections is critical to prevent future sensor faults. While not a catastrophic issue, ignoring it can lead to fuel system damage if water contamination goes undetected due to faulty readings. A full diagnostic scan would confirm if your issue matches this common failure pattern with the water-in-fuel sensor system.

Thanks for sharing your experience with the sensor fault issue. The symptoms do sound identical to what I faced. Before I take it to a shop, could you share roughly how much the wiring harness replacement ended up costing? Also curious if youve had any other moisture sensor related problems since the repair was done? The fault codes from my car diagnostics are pointing to the same electrical fault with the water sensor that you described. Just want to make sure Im prepared for the potential cost and confirm the fix was reliable long-term before moving forward.

Took my Touran to a certified shop last week to fix the water sensor malfunction after sharing the initial experience. The repair bill came to 95€ for replacing the corroded cable connections at the sensor plug. Good news, the sensor testing came back perfect after fixing the wiring issue. No further sensor issues or check engine lights since the repair. The car diagnostics confirm everything is working as intended now. The shop found exactly what I suspected, moisture had damaged the connector, causing unreliable readings from the water sensor. From my recent experience, this is a straightforward fix once properly diagnosed. The repair cost ended up being quite reasonable compared to what I initially feared. The engine runs smoothly again without any electrical fault warnings. Looking back, getting the sensor issue fixed promptly was definitely the right call to prevent potential fuel system complications. If your fault codes match what I had, you should be looking at a similar repair scope and cost.

Thanks for the advice. I took my Sharan to a certified mechanic who specializes in auto electronics yesterday. The diagnosis confirmed the faulty water sensor wiring harness, exactly as described. Total repair cost was 110€, slightly more than expected due to some additional corroded pins they found during the sensor testing. The mechanic showed me the deteriorated connections and explained how moisture had caused the issue. The car runs perfectly now, no more rough running or check engine lights. The new wiring harness was properly sealed to prevent future moisture sensor problems. Really glad I asked here first, saved me from going to shops that might have replaced parts unnecessarily. Just wanted to close the loop and confirm this common water sensor fault was resolved exactly as suggested. The repair was straightforward once in qualified hands.