Re: A4 Driveline Shudder Datapoint

[dan_masi@MENTORG.COM (Dan Masi)]

> Subject: Re: A4 Driveline Shudder Datapoint
> Bob Cotton wrote:

> > Could this shudder be something in the anti-knock regulator that
> > is invoked with lower octane gas?
> >
> > Do people who experinece this regularly run on regular or premium
> > gas?

Interesting!  I alternate between premium and regular (not
regularly, just depending on what gas station I'm at, what
prices are, and how cheap I'm feeling).  Just before I saw this
mail, I had filled up with Mobil Super after the tank had
run into the almost-dry area on the gauge.  I've noticed in
the past that sometimes the shudder is very easy to reproduce
and sometimes not.  So, with that in mind, I went out and
tried very hard to reproduce the shudder with my tank full
of premium gas.

Turns out that yes, I can still get it to happen, but
1) it's very difficult, and most importantly,
2) it's not nearly as pronounced as other times that I've
   seen it.

I'll fill up on regular next time and try it out for comparison.
Perhaps it really *is* an engine management issue, like poor
feedback design in the ECU or something.  IF so, that would
be an awfully easy fix for Audi to make...

Dan Masi
'96 A4Q