Failed emissions due to timing? Can it be?

[Dave Haupt]

The Audi dealer mechanic's official word on it is that
there is no running specification for initial timing
on the turbos.  As another poster noted, the ECU
automatically sets the timing based on many
parameters, including temperature,  Therefore, if you
connect a timing light, at idle, there is no
"expected" setting.  At least, that's my
understanding.

And, for what it's worth, the crankshaft pulley on
mine has no timing mark.  Instead, the timing mark
associated with the crankshaft is on the flywheel,
which, as far as I know, has no rubber damper, so it
cannot slip.  If it did, the ECU would get the timing
all wrong anyway.  Mine's an MC, though - the 3B may
be different.

Dave



--- Dan Cordon <cord4530 at uidaho.edu> wrote:
> Sorry, I should explain better. You're right....the
> crank pulley can 
> only go on one way. I'm also pretty sure that
> there's nothing 
> missaligned between the crank position, camshaft,
> and distributor. If 
> there were it probably wouldn't run, or if it did it
> would run pretty 
> rough.
> 
> What I *think* has happened is that the mark on the
> front is no longer 
> referenced to TDC. I've heard many times (Cody very
> recently) where the 
> timing mark on the pulley has rotated relative to
> the keyway in the 
> crank pulley it's affixed to. (deteriorated rubber?)
> 
> If this were the case, then the engine would be
> running just fine (and 
> pass emissions great too), but when the tech person
> puts a timing light 
> on the engine and finds the mark on the pulley....it
> will be way off 
> from what the actual timing is. Didn't Cody mention
> on the last 'get it 
> running' quest that the mark was nearly 180° off?
> 
> Assuming this is what happened, (and the pulley with
> the timing mark 
> isn't too loose) you could re-mark the timing mark
> to coincide with TDC. 
> This way when the tech person checks timing again
> they'll find it 
> perfectly normal.
> 
> Alan Cordeiro wrote:
> 
> > Dan,
> > 
> > Not sure I understand where the five degrees could
> come from.
> > 
> > 1)  The crankshaft pulley can only go on one
> way...not sure how
> > it could go off by five degrees.
> > 
> > 2)  If the pulley were off five degrees somehow,
> you still end up aligning
> > the timing marks on the CAMSHAFT pully to the
> (rusty, almost invisible)
> > timing mark on the flywheel. The engine reads the
> flywheel teeth and
> > once-per-revolution pin, and uses this as the
> basis of timing.
> > therefore, if your timing check was good....the
> front crankshaft position
> > should not matter at all.
> > 
> > Alan
> > 
> > 

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