The preliminaries: I'm doing a deluxe timing belt job with valve cover gasket/ cam chain tensioner pads on an '02 A6 2.7t, for a customer (I've gone semi-pro in fixing VW-Audis). To put in the crank lock pin I removed the left (driver's) pressure hose from the turbo to intercooler. When I did this about a half a quart of oil poured out! So; I removed the same hose from the right side, and only a couple tablespoons came out.
More info: The car has 165k on it, and it has been severely neglected. This is the car's first timing belt job, I've never seen a timing belt so glazed and cracked! Oil was awful! PCV system does look nasty. Car is throwing four very relevant codes: 16805 & 16815 warm up catalyst banks 1 & 2, and 17861 & 17865 exhaust gas temp sensors 1 & 2. Six weeks ago I cleared those codes and found a vacuum leak. The PCV check valve (has 4 hoses attached to it) was broken. Maybe it caused more oil from pcv to leak into left pressure hose. Now those codes are back.
My thoughts: Oil in left pressure hose could be entirely from pcv system. Its had 11 years and 165k miles to fill that hose with 1/2 qt. of oil. I will definitely replace pcv valve and clean pcv hoses. The cat and egt codes are probably from oil leaking from the turbos and clogging the cats and thus increasing exhaust gas temps. What else would cause the cat and egt codes? Ring failure maybe? But these cars aren't known for that. I have a 2.8 A4 with 165k, and have no problems with cats or egts. The turbos don't whine, so the bearings are probably ok, but at this mileage, they are probably worn out. How many miles are the original k03s good for? If it was my car I would pull the motor and replace the turbos with k04s. I don't think my customer wants to spend much on the car. Even at my rates, ($50/hr.), and cheap parts prices (about $800-$900 for a pair of k04s), the repairs will quickly eclipse the value of the car. I will explain to customer that if he has me do the work, the car will be worth a lot more to him than the car's resale value; thus becoming a "keeper," and a car worth committing to for 5 years or more.
What will probably happen: I'll finish timing belt job, replace pcv valve and clean pcv hoses, and I'll also clean intercoolers with mineral spirits. Maybe I'll pull EGTs and see if they are oily. I will completely inform customer and discuss options. After six months to a year maybe customer will bring car back to me. I'd like to re-check pressure hoses for oil. I'd like to remove cat downpipe assembly and look for oil. I'm about 75-90% sure I'd find them oily and greasy. I'd like to replace turbos and cat/downpipe assemblies. Now would be a better time than later because i've done half the work towards pulling the motor.
Information is key. Any insight from anyone would be greatly appreciated. Is my thinking correct? I will update thread as I continue with this job and gain more info.