I posted earlier in a thread that the Black Stone oil analysis showed possible coolant in the oil based upon sodium (215 v. 18 ave.) and potassium (20 v. 4 ave.) levels. Prior to this I had to add a small amount of the coolant to the coolant reservoir. I had thought it might be that I didn’t get all the air out of the system so it needed a top off. I was (and still will) send in another sample in to Blackstone to see if the numbers are higher.
Today when starting an oil change I noticed a small amount of that telltale chocolate shake residue in the oil separator when removing the vent hose (which broke from being very brittle…$200 part on order! >:( ).
So…now I have to decide how far I’m going to dig into this, which is where I’m looking for some advice.
I am set to do a carbon clean in April. I was also going to do a power steering drain and had intended on removing the bumper. At that point I guess I could remove the oil cooler and test for leaks for a half day more work. Foolishly did not think to test cooler when I replaced oil cooler o-rings. If the cooler turns out to be bad, I’ll just tell myself the failure occurred recently and I wouldn’t have found it then. New oil cooler is somewhat reasonably priced $267 on AudiUSAParts.com (again, stupid vent hose is ~$180 online, $208 at local dealer)
Beyond that, I’m not sure there’s anything else I can check without doing an engine drop and tear down, is there? There’s some tubes at the back of the engine that eng92 and gregoh pointed out, but those are buried inside.
EDIT: fixed sodium/potassium numbers