Fairly new member here and wanted to say thanks. Last year had picked up a 2001 Audi A4 and she liked it so much, I picked up 2004 A4 with the Ultrasport package. It needed work, but for the price I couldn't pass it up. I knew it needed the valve cover gasket and thermostat (found great info on changing both). It also had a rough idle. Running VAG-COM, found the P1297 and P0300 codes (as well as the individual cylinders). So from reading on here, this led me to look at the PCV system, and found this.







The crankcase breather to the PCV had cracked (and also came apart when removing it was so brittle). Also the hard tube from the PCV to the elbow had split. So I replaced all the components (wish I had seen 034 Motorsport silicone components before I did, oh well). I did it without removing the intake, and my hands are only slightly worse for wear. Car is now running perfect, nice smooth idle and no CEL.

Wanted to say thanks for the info form those who post on here.

Here is the car, and other than the original owner keeping the 18" rims, it's incredibly clean.

 

Wilkkommen (officially) to the forums!

glad you got everything sorted. that is definitely an ugly looking breather hose, but I've seen (pictures) worse.

car looks great

have fun