I bought my '07 S6 with 150k miles from a family friend about a year ago, and while it was in overall good shape, she definitely needed some TLC. It’s not my daily driver, nor is it my only project, so it’s not nearly as repaired as I would like, but, it’s getting there.
My biggest concern with it for a while now has been that it loses a lot of oil - even without driving it much (I probably put ~1,200 miles on it in the last 13 months), it was needing about a quart of oil every month - and the oil it was losing seemed to be hitting the exhaust and smoking a lot. It also seemed to not smoke (much) if I kept the RPMs lower than ~2,500, but if I revved it up it would smoke more.
From some research on here, I decided to start with a carbon cleaning and replace the oil filter O rings, which definitely helped with the amount of oil I was losing, but I was still burning oil on the cat, seemingly mostly from the driver’s side (US). This past week I replaced the valve cover gaskets and PCV/Oil Separator and I think I’m done burning the oil, however, when wrapping up the project and tidying up my tools, I let it idle for a few minutes before going on a test drive and I noticed it was absolutely pissing oil out the front center of the engine. I decided I’ve replaced this much of the oil seals (and those valve cover gaskets were brittle), I’ll do the front main seal and the oil cooler O rings to hopefully resolve this.
From reading around this site, I see that the PCV/Oil Separators have a tendency to create high crankcase pressures, SO, my question is - Do I have a faulty PCV that’s giving me high pressure and that’s why it’s suddenly leaking out the front main seal, or, now that it can’t leak out the valve covers, is it just coming out of the next weakest point?
Thanks in advance 