compression test #'s help

Bernard Littau bernardl at
Wed Aug 28 15:21:02 EDT 2002

Hi Ron,

>   Little more info for those of you following allong,
>  Under a heavy foot just starting off in 1st there is
> a cloud of smoke out the rear pipe but not under
> normal driving,
>  looks to be white/grey smoke

The rules of auto smoke as learned by Bernard:

Black = rich, too much fuel
white/grey = water or coolant (or brake fluid)
blue = oil

I'm not convinced you are burning oil.  Are you loosing any coolant?

>  there's all so a lot of oil in the lower intercooler
> to turbo hose,
>  and in the turbo hose going to the fuel distributor,
>  all so oil in the Michelin man hose as well

This is fairly normal, although the oil in the hose from the airbox to the
turbo is curious (I assume this is what you mean by "the turbo hose going to
the fuel distributor")

>  I did the compression test as per Bentley
> instructions did then twice to make sure they were
> done rite.

Those numbers look fine for an old car.  The one outlier is curious.  It is
possible that the one higher compression cylinder has a valve stem leak, and
the extra lube is making the piston/cylinder seal a bit better.  What do the
plugs look like?  Just for fun, do the compression test again, all five
cylinders, then squirt in some oil into each cylinder before you test that
cylinder, and do the test again.

>  I just changed the oil in the car on Sunday and on
> Tues I had to add a full quart, the oil wasn't showing
> on the dip stick and the car only went 100 miles in
> that time.

Yikes! Is this your normal loss rate?  Did you account for the filter being
empty, or did you just top it up after the oil change, before the engine was
turned over?  You're not burning this much oil, or you would know it.  Find
the other oil leak(s).  My oil pan gasket was leaking ($15 part), start with
that, perhaps.  Consider power washing your engine and tracing the leaks.

>   Another thing I mentioned the oil loss to my local
> Audi Tech whom I have a VERY close relationship with
> I've known him for like 10 years so I know he wont
> tell me some bullshit story to try and sell me a turbo
> or anything but he has said that it's the turbo and he
> wont change his mind,

Make a deal with him :-)  If putting in a new turbo, and only putting in a
new turbo and not doing anything else, fixes the oil loss and the puffs of
white/grey smoke, then you'll pay for the turbo job.  If not, he pays for
the turbo job.  Confidence is easy when it's not your money.

>  my question is whats the likely hood that it's the
> turbo over the valve seals? on a scale from 1-10.
> Thanks for the additional info

Door number one or door number two?  Wait, I pick door number three -- head
gasket and leaking coolant.

Boy that's a tough call.  Neither the valve stems or the turbo are
inexpensive enough repairs to just try.  Plus, I'm not convinced it's oil
smoke.  Get more opinions; I think some more diagnosis is in order before
you pick a repair.


Bernard Littau
Woodinville, WA
'88 5ktq

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