Tiguan Stalling: Faulty Tank Vent Valve Alert

Had similar issues with my 2014 VW Golf GTI. The check engine light came on with stalling symptoms, and the automotive repair revealed multiple problems with the tank ventilation system. The evaporative emissions system had a clogged purge valve and blocked ventilation hoses. The main issue was carbon buildup restricting proper airflow. When these components get clogged, the fuel tank pressure cant normalize, leading to those exact stalling symptoms at idle. The repair required cleaning the entire ventilation system and replacing the purge valve. This is a serious issue since it affects both engine performance and emissions. Left unfixed, it can damage other components of the fuel system. These symptoms match your Tiguan case closely. The repair needs specialized diagnostic equipment to properly test the tank pressure and identify exact blockage points. Best to find a shop with experience in VW fuel system repairs, as incorrect diagnosis can lead to replacing wrong parts. The stalling issue typically worsens over time as the system gets more restricted. Getting it fixed properly the first time prevents repeated repairs and potential fuel tank damage.

Thanks for sharing your Golf GTI experience. The EVAP system issues you described sound exactly like what I am experiencing. Before I book a repair, could you share what the total cost was for your purge valve replacement and system cleaning? Also curious if you had any related problems pop up since the fix? Looking to get a rough estimate and make sure the repair holds up long term. The gas cap and fuel tank are both original parts on my Tiguan, so trying to determine if those need attention too.

Since my Golf repair last year, I can confirm the EVAP system fix worked perfectly with no recurring issues. The mechanic cleaned out all the clogged hoses and ventilation lines, which made up most of the 175€ repair cost. The purge valve malfunction diagnosis was spot on, and getting it fixed properly prevented any tank ventilation problems from coming back. Your original gas cap and fuel tank should be fine if they are not showing signs of damage. The check engine warnings usually point specifically to the ventilation system components rather than the tank itself. The automotive repair shop will test the entire system pressure to confirm this during diagnosis. Based on the similarities with your Tiguan symptoms, I would expect comparable repair costs if the issue is indeed just clogged ventilation lines. Make sure they do a complete EVAP system test to rule out any additional problems. The investment in proper diagnosis helps avoid replacing parts unnecessarily. Better to address these tank ventilation issues early before they cause more extensive fuel system damage. The stalling should resolve completely once the system is cleaned and properly functioning again.

Thanks for the detailed feedback. Finally got my Tiguan fixed last week at a certified shop that specializes in emission system repairs. The diagnosis confirmed exactly what you experienced, a faulty purge valve and clogged ventilation lines. Total repair came to 210€, slightly more than your cost but included a full EVAP system inspection. The mechanic showed me the carbon buildup they cleaned out of the system. Been driving for a week now and the idle is smooth with no check engine lights. Really glad I switched repair shops. The new team actually took time explaining the fuel tank ventilation system and showed me the cleaned versus clogged components. Much better experience than my previous repairs. The stalling is completely gone and engine runs perfectly now. They also checked my gas cap and tank, both were fine as you suggested. Good call on getting it fixed before more damage occurred.