Oil Consumption, T44TQ

[Larry C Leung]

Hello List,

Well, at least some things in life are going right.

I believe I have ID'd some of my car's difficulties. Some of the
stumbling is
likely to do with a (now that I have the stock ECU mounted, JUST to be
sure)
bad O2 sensor, at least that's the code that's been thrown. It doesn't
pop up
without pulling codes (i.e. no check engine light upon start-up or
running, it
just shows when I pull codes), which surprises me,  I would have thought
that O2 sensors would throw an automatic Check Engine light.

The other thing was, when I changed the ECU back to the stock one, I also
removed the wastegate Charlie Spring, which would of course cause an
overboost condition. It turns out I accidentally knocked off a single
wire
connector (single wire) that is in the vicinity of the firewall and
wastegate.
Now it just stumbles mildly, at part throttle, the problem is you have to
go
through the stumble/balk that feels like throttle resistance (it's not)
on the
way to full throttle. Once at full throttle, boost builds normally and
power
seems normal.

Anyway, thanks to Robert, Joshua, Ron, Huw and Gary for all of your
suggestions
for the power loss, I can't confirm I've licked it yet, but hopefully,
it'll just be the O2.

Now, the oil consumption issue. In going through the rest of the engine
(cleaned
the air filter, the crankcase breather, checked the plugs/wires/rotor
visually) I noticed
that the turbo coolant cross-over pipe is covered with an oily film, as
is the port side
of the head, at least near the front of the engine. It is most DEFINITELY
below the
valve cover gasket, and there is no oil in the tray over the intake
manifold. No other
visible oil leaks and yup, the oil covered parts were clean in August.
Any ideas where
the oil could be coming from? (the oil cooler lines are also clean).

TIA!

LL - NY