jrhgto

When I had the PCV issue on my A6 I was burning a quart every 3K miles...After the fix, it went to about 1/3 of a qt every 6K miles. If I was burning a quart every 700 miles, I would make it my top priority to figure out why. that much oil loss doesnt seem like a PCV issue.....That is beyond the definition of excessive. consumption. Not sure why you want to ignore that.

AlexA4B8Fan

When I remove the oil filler cap with the engine running, there is some suction making removal a bit harder, but not a massive amount. Once removed, I can detect a different rpm. Is this normal? I seem to recall that removal of oil cap used to be more difficult with engine running.

jrhgto

I believe some resistance is normal...If the PCV is bad it should be extremely hard to remove the cap during idle. The change in RPM/bog is normal as you are creating an air leak in the system...
If you are losing that much oil, do you see white smoke out the tailpipe?

AlexA4B8Fan

Thanks for the tips, but now I am really confused.
In addition to my A6 I have a Q5 with the same exact 3.0L. The Q has 100K miles and I never have to add oil, and my A6 has 172K, and as mentioned I add 1Qt every 700 miles or so. So I had them both running in my driveway, side by side. I removed the A6 oil cap with modest resistance from the suction. I then went to the Q, and It was significantly harder to where I almost needed a tool to remove it. So the oil cap theory is working opposite what I am hearing, as the Q has no issues I know of.

Thoughts???

jrhgto

not sure....I just tried it on my 2012 3.0T A6 w/165K miles. cap was fairly easy to remove but could feel the suction. No known current PCV issue on the car, did have PCV replaced at 50K miles.

raj99

@AlexA4B8Fan so you ever figure our the large oil leak going on in your C7? At the rate of leak you've got going on, you pretty well go through a full oil change by the time it's actually needing to be changed.

I'd strongly suggest you get the car diagnosed by a professional vs. yourself and get this fixed, since you're leaking oil like a sieve and these things tend to only get worse.