I have a 2002 180Q TT. I have a read a ton of places about the po171. I have not however found a solution. The code comes on, I clear it and it comes back on sometimes 90 miles later sometimes 300 miles later. I have replace the three hoses from the valve cover to the top of the oil filter area. The dealer told me they are the ones the break. They were indeed broken so I replaced them. I have gone through the rest of the car and can't find any bad check valves or leaking hoses. I check and clean the MAF, thats not it either. The car runs fine with the code on, but I hate staring at it. I am about to send the ECU in for an upgrade, but I'd like to get this taken care of first. Any idea's?

 

Nothing?

 

Whats po171?