Re: New Audi A6 2.7T 6 speed in the garage

[Paul Nicholson <paul@eisusa.com>]

At 12:59 -0800 11/16/99, <isham-research.freeserve.co.uk@pop.pol.net.uk> wrote:
> > When I used to do instrumentation and electronic consulting for Toyota
> > Racing Development, I heard plenty of (old wives?) tales about people
> > that decided to cut off fuel when the engine was braking and paid for it
> > with burned pistons.
>
>Happens on the MB engine.  Part of the high output enrichment comes from
>a fuel frequency valve input.  Close the throttle at full chat and the
>engine goes lean _very_ suddenly.  If the ECU is badly chipped (voltage
>divider vs proper reprogramming) the engine can go lean and hot enough
>to burn a hole (usually in #5, sometimes #4) or shatter the exhaust
>manifold.

But what if you inject zero fuel? The only heat would be the compression of the small amount of air that got in the piston on the intake stroke with the throttle closed. There would be no heat from combustion.


>Not an old wives' tale.  Too many holes in too many pistons.
>
>--
> Phil Payne
> UK Audi quattro Owners Club
> Phone +44 7785 302803  Fax +44 870 0883933