I did the Seaform intake cleaning not to be confused with the oil/sluge removal way. I've done it a couple of time in the past on my MK3 Jetta VR6 but this was my first time on the S4. Super easy to do on the S4 since the vacuum line to use is the same one connected to the Boost gauge. I do want to add to the existing DIY's out there, is that you need a second person to do this. Luckly my wife was willing to help. Basically you need the second person to keep the car reving around 1500 RPM's. If you try to do it with the car at idle the car will die. Anyway, since this was the first time for the S4 there was a huge smoke show. I wish I had taken some pictures. Looks like my car was on fire or something but that's just how it works. After letting it sit for 15 mins I drove maybe 20 miles before all of the seafoam was cleared out (smoked stopped). The car for sure seems to have a lot more low end tq and the fuel economy has improved maybe 1-2 more mpg. I recommend this for anyone wanting to make sure there car is running in top shape. Here is a link to the Audi S4 Seafoam treatment DIY I used.
Also changed the Oil Filter. Nothing too exciting this month.