VW Phaeton Stalling: Fuel Tank Vent System Fix Guide

Had similar symptoms on my 2004 VW Touareg V8. The check engine light kept illuminating and the engine would stall at traffic stops. Initially thought it was the gas cap, but a proper diagnosis revealed clogged ventilation hoses in the emission system. The fuel tank pressure sensor was getting incorrect readings due to blocked lines, causing the engine management system to malfunction. The fix required cleaning the entire evaporative emission system and replacing several deteriorated hoses that had become brittle with age. This was actually a serious issue because prolonged running with a compromised ventilation system can damage other components. The vehicle would eventually fail to start if left unaddressed. The repair involved dismantling parts of the fuel system to access all affected areas. After the repair, the engine light cleared and the idle problems disappeared completely. Would recommend getting it checked soon, as these symptoms typically worsen over time. This is a known issue on several VW models from that era with similar fuel system designs.

Thanks for sharing your experience. My VW Phaeton had identical symptoms last year with the engine light and stalling issues. Got it fixed at a local VW specialist who also found problems with the tank ventilation system and several cracked hoses. I am curious, what was the total cost for your repair? After a few months, have you noticed any related issues coming back? The fuel tank pressure sensor readings on my car have been stable since the fix, but I like to hear long-term experiences from others who dealt with similar problems.

After getting the tank ventilation valve malfunction fixed at the shop, I have had zero issues with the engine light or stalling. The repair cost came to 175€ for cleaning and replacing the clogged hoses in the evaporative emission system. The purge valve and connected components are all working perfectly now, maintaining proper fuel tank pressure readings. Its been over a year since the automotive repair and the system has remained stable with no warning lights or performance problems. The investment was worth it since leaving these ventilation issues unfixed can lead to more expensive problems. My advice remains the same, when dealing with these symptoms, its best to address them quickly before they affect other engine components.

Thanks everyone for the helpful replies. After reading your experiences, I took my Phaeton to a certified shop last week. The mechanic found multiple issues with the purge valve and deteriorated ventilation hoses in the emission system. The total repair came to 250€, which included replacing the faulty components and a thorough system cleaning. The check engine light finally stopped appearing and the car runs smoothly at idle now. Really glad I got it fixed rather than waiting for more problems to develop. The shop also did a complete diagnostic scan which showed no other emission system concerns. Will monitor the fuel pressure readings over the next few months just to be sure everything stays stable. Based on your long-term experiences, feeling confident this should resolve the stalling issues for good.