VW Lupo Fuel Tank Vent System Causes Engine Stalls

Had similar symptoms with a 2006 VW Polo 1.4 FSI. The fuel efficiency dropped significantly and the engine would stall at idle. Diagnostic tests revealed a faulty purge valve and a clogged activated charcoal filter in the EVAP system. The leak detection pump showed system failure, confirming issues with the fuel tank ventilation. The charcoal filter was completely saturated, preventing proper vapor recirculation. This caused irregular fuel mixture and idle problems. The fix required: Complete EVAP system inspection, Replacement of activated charcoal filter, Purge valve replacement, System pressure test This was a serious issue that needed immediate attention, as it affected both emissions and engine performance. Leaving it unfixed risks damaging other components and further reduces fuel efficiency. Common signs pointing to this problem: Stalling at idle, Check engine light, Strong fuel smell, Failed emissions test, Rough idle after refueling Recommend getting the EVAP system thoroughly checked, particularly the charcoal filter and purge valve components.

Thanks for sharing your experience. I had exactly the same symptoms with my Lupo last year. The emission control system inspection revealed similar issues, and replacing both the purge valve and charcoal filter solved the problem completely. Do you remember roughly how much the repair cost in total? Also curious if everything has been running smoothly since the fix or if you noticed any related issues popping up later? My car has been fine so far, but I like to know what to watch out for.

Great to hear your Lupo got the same fix that worked on my Polo. The fuel tank ventilation system leak was completely resolved after replacing the defective activated charcoal filter, which cost 275€ including labor. The EVAP system has been working flawlessly since the repair, no check engine lights, stalling, or emission control issues for over a year now. The pressure sensor readings have remained stable, showing no signs of new leaks. Regular maintenance checks show the new components are holding up well. Fuel efficiency returned to normal and the engine runs smoothly at idle. Just keep an eye on your fuel consumption, any sudden increase could indicate the EVAP system needs attention again. But these parts typically last several years when properly installed.

Since the repair three months ago, my Lupo has been running perfectly. The total repair came to 320€, which included the new purge valve, charcoal filter, and labor costs. The mechanic I found did a thorough job with leak detection and air flow testing to make sure everything was sealed properly. The difference in performance is remarkable. No more stalling at idle, the check engine light stays off, and the fuel efficiency is back to normal. The pressure sensor readings are steady now, showing the system is working as intended. For anyone dealing with similar issues, I suggest finding a shop that specializes in VW fuel systems. The previous mechanic missed these problems entirely, but the new one diagnosed it right away with proper diagnostic equipment. Worth every cent to have it done correctly the first time.