re '98 A6 2.8 won't start- mechanics are at a loss...

["Smith, Kirby A" <kirby.a.smith@lmco.com>]

Tom Nas <tnas@euronet.nl> asked:

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Hi all,

Got this request from a friend of mine who works as a mechanic at a VW/Audi
dealership. It's got all of them and the Dutch importer stumped, it would
be great if anyone on this list could help-

Subject: '98 A6 2.8 FWD automatic, 60k km

Car stopped running a couple of weeks ago, just died on the highway. It's
been in the 'shop since.

All systems check out, no fault codes. Fuel and spark verified, timing belt
OK and not jumped a tooth. When you start it, it turns very quickly as if
there's no compression (which is OK when tested, BTW). Not even an attempt
to start, nothing.

My first impression: plugged exhaust/cat. Any other suggestions?

TIA for your help!
??????????????????????

I can't imagine a condition that would allow the compression to be good
under test and bad under starting, which is the way one does a compression
test.  However, here is a stab in the dark to supplement your cat theory,
which is better, although it doesn't explain the easy cranking.  At the Mt.
Wash race I viewed a cylinder head from an Audi V6 that the quattro club
apparently owned.  The cams were linked by a chain between them.  The chain
phased the cams and was externally controlled.   Maybe there is some way the
chain assembly could be defective.

kirby