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

"Bernard Littau" <bernardl@acumenassociates.com> wrote:

>>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?
>I hope there is more to the story than what you wrote so far.

Not a lot, but I'll answer the questions as you ask 'em.
>(Warning, Bernard the amateur home mechanic shooting off his mouth, but here
>Has a compression test been run?  What are the results?

That I did write: compression's OK.
>Very weak spark could become no spark on compression, but still spark a plug
>when a plug is energized outside of the engine.  Have you tried an inductive
>timing light?

Verified this with my friend- yes, they have.
>How is the air intake path?  Throttle body shut?  Obstruction?

Nothing there. They've disassembled everything.
>The ECU make be bad, too.  No codes may be due to broken ECU.  Can you swap

That was my first suggestion, too. He said systems checked out OK, ECU
self-diagnostics were fine. There was no second car available for ECU
swapping, but it could be arranged with the help of the importer.
>Cat plugged might do this, but I've never seem one be so plugged the car
>won't start -- they usually go slowly.  Doesn't the 2.8 have multiple cats?

I think so, yes. No data for this offhand (ETKA doesn't run on my home
system, I'll check it at work tomorrow).
>No fuel also a possibility, how was this verified?  Put some gas into the
>intake manifold and try and start it.

Fuel pressure measured at the injectors, checked out fine.
>Interesting problem.

I'd say so... thanks for your suggestions so far!