[s-cars] What is wrong with my engine?

[CyberPoet]

Dear Clayton,

Given:
The result is that your oil volume became dangerously low and the two
seemingly described side effects are (a) burnt rings or valve seals,
and (b) coke/ash build-up in the turbo (from inadequate oil feed at
some time previously). The 15W oil being burned is almost guaranteedily
not a contributing cause, but a symptom of prior problems
overlooked/not noticed in timely enough a manner. Note this ignores the
power steering fluid issue, which is separate unless someone has been
intentionally tampering with your car.

It would seem one of three things is happening, as far your symptoms go:

1. (least likely) Someone is intentionally messing with your car to
upset your wallet and lifestyle.

2. (infinitely more likely) Loose or mis-seated oil drain plug, or
small nick in the oil cooler/oil cooler lines, or loose spark plug/bad
thread is/are permited the oil to leak out under pressure at some
point, or possibly at stand-still (most likely at pressure, where the
car's speed is carrying away the evidence). Result: inadequate oil
level at some point, permitting rings to wear and turbine's oil-cooled
bearings to build up ash from inadequate lubrication.

3. (another reasonable possibility) The months(?)/years(?) of running a
very light weight oil (5W-xx) and initial pumping losses (indicated by
the oil warning light staying on for longer than a second when starting
the car on cold days) permitted some parts in the engine to wear
prematurely and excessively. Recheck OEM owner's manual for minimum oil
weight specifications and never dip below it again (whether damage is
found or not) -- depending on your year & engine, that could mean
anything from 10W-30 to 20W-50 to straight 30 weight. I don't think any
pre-2000 Audi is rated for a 5 weight oil basis (use their
documentation for verification -- I certainly know mine isn't).

Diagnosis, pro-level:

1. Exhaust analyzer: look for excessive hydrocarbons (burning oil - if
excessive, suspect rings, valve seals, etc);

2. Pressure leak-down test for each cylinder (isolate the location).

3. Check the cam, crank seals, both fore and aft, for leakage & weeping
under pressure.

4. Check the oil pressure at various points in the system with a
separate pressure tester. Be sure to test the leads to and from the oil
cooler (for a pressure loss across the oil cooler), as well as the
turbo feed lines.

5. Drop the oil pan and look at the main journal bearings -- the metal
from burnt rings can induce bearing damage at the main bearings.

6. Yank the head and check the pistons and valves.

7. Rebuild engine. Remember to consider a port & polish at this time,
if you can afford it...


Diagnosis, amateur-level, to start with:

1. Cat litter or fresh craft paper on the ground across the entire
over-night parking spot, including under the front bumper. Drive it as
usual, and then park over the litter and let run 10 minutes before
shutting down for the night. Check in the morning for fresh spots.

2. Try an engine oil flush, followed by a light-oil flush (a straight
10 weight run-in for 5 minutes then redrained), and then move to a
heavier oil (20W-50). Recheck consumption and turbo temp while praying
that the initial oil starvation was caused by a large clump of gunk
that was just flushed out (still doesn't fix the damages, but does
eliminate the source if you're lucky). Side benefit: will help remove
the ash from the turbo bearings in the process of the flush. Recheck
for oil consumption every 100 miles for the first 500. If consuming
more than 1/2 liter per 500 miles, you must go the professional repair
route. If it doesn't eat that much, change your oil at 1000 miles and
examine the oil.

3. FOR EVERYONE: invest the $24.95 for a professional grade oil filter
separation tool to open up the oil filter at time of change. Check the
filter element for metal, indicating unexpected wear before it becomes
a major repair nightmare. Given experience, you can even tell what is
going bad from the types of metal found (when present). Check your oil
filter for metal particles, etc.



Either way, Clayton, this is probably going to get horridly expensive
before it gets any better. I wish you the absolute best and the minimal
aggravation with this.

Good Luck
=-= Marc S.A. Glasgow
www.cyberpoet.net


CLAYTON WROTE:

I have three concerns that have to do with my engine lately and I am
just now
sure what to go from here.  I hope some of you guys out there will be
able to
shed a bit on light on any of these....

1.   Less than 2K miles ago I had the oil changed.  I always do M1 but
for the
summer I decided to run 15w this time (any complaints there?).  Well, I
realized today that the engine was tinging (what sounded like all 5),
so I
checked the oil and sure enough it was dangerously low.  It took two
quarts,
and the oil in there seems a bit black.  Not too sure, it was getting
dark,
but I have never had that happen.  My "Oil" warning has come on before,
but
only on cold days and then it goes away.  This is even if I know I have
plenty
of oil.  But in the case, it never showed at all.  I was low enough I
think it
would have warned me but it did not.  Can anyone explain why, after I
change
the weight of my oil, I loose almost all of it in 2k miles?  I have not
noticed any burnt oil in my exhaust nor any on the ground after being
park.

2.  After this same drive (getting some oil back in to get it up to safe
operating level) I noticed my turbo was amazing hot after shutting the
car
off.  I have never noticed it running so hot, especially considering I
did not
go over 3psi since the last time it was off.  My last drive I did not
break
say 7psi.  So for not using my turbo at all, I do not see why it was so
hot
tonight after all the oil issues.

3.  I used to loose most of my power steering fluid in about a 2 month
period.
Then starting two weeks ago, I lost most of it in a weeks time, and
then it
has happened in about 4 days time now.  I am not so sure what is going
on and
why all of a sudden I am losing all my mineral fluid.  Any suggestions
out
there in terms of items to replace, check, tighten and the like.

As you can tell, I do not have a Bently yet.  So could someone also
tell me
where a good place to pick one up so some of these things I can check
before
coming to the list.

I do appreciate all of your help out there.  I am hoping I can take
care of
some of these little quirks so I do not have to get rid of her....
CT "The Clutch" Howes