Hey guys I have a 01 s4 and have a CEL, vag-com says smog system, improper ventalation. and when I fill up, the filler hose builds pressure causing the pump to shut off every 5-10 seconds,. Has any one ever had this problem or can anyone give me a clue as to where to start?

 

What is the exact fault code, there is no "smog code" per say.

 

Fuel tank purge valve might be stuck.

 

I know there is no smog code, I forgot the code. I'll have to plug it back in and find out. Where is the purge valve located