So I just bought a 2012 Passat TDI with 91k kms. An hour after I bought it, I got a CEL for NOx sensor. I cleared it, but it came back every 100km or so. Figured I have to do a NOx sensor. Then I get 350km until no restart possible. Check the adblue tank and it is physically full. Check it with VCDS and it shows 99% full. Took it to the dealer to have the wiring harness recall done hoping that would fix it. After multiple forced regens the dealership says I need a new NOx sensor. I had it replaced, but still they can not get the countdown to go away. No codes are being thrown. The last thing they tried was to take it on an 80km test drive while forcing a regen. Still no luck, and now there aren't even enought kms left before restart to drive it back to my place. Any ideas would be appreciated. Apparently the dealership is out. They had better not hand me a $2k labour bill for guessing what's wrong with it. I'm sure hoping somehow it can be covered under warranty.