I've got the P0401 code on my Jetta. Will go away usually after a few drive cycles, or after I erase it with the VAG-COM interface I've got. Always comes back. Insufficient EGR flow code. Before I started checking the exh. flapper valve as was here recommended, or the EGR valve, etc., I decided to call the dealer I'd been taking it to. They did the last free service a couple months ago. It's got 38600 m. on it now. First thing out of the mouth of the service lady that took the call was that the EGR valve was not covered when I told her the emissions systems were under a 80,000 m. warranty. Said the service manager would be back on Friday, and I told her I'd call back then and talk to him. According to the documents that came with the owner's manual, she was right. Volkswagen says the EGR sys. is not covered on the 80,000 m. warranty. Since it's emissions, I don't see how they can get around the Feds mandated 80,000 m. warranty? If anyone has some advice as to how I can hold their nasty conniving feet to the fire when I call back Friday, I'd sure like to have it. Thanks in advance.