[s-cars] Stumbling under acceleration.....probable boost leak? Or...

Calvin Craig calvinlc at earthlink.net
Wed Nov 25 18:40:12 PST 2009

Stumbling under acceleration.....probable boost leak? Or...Most common spot
that is easily missed while visually inspecting is the lower "michelin man"
hose.  Usually the holes develop right by the creases where the are hard to


  -----Original Message-----
  From: Ben Swann [mailto:benswann at verizon.net]
  Sent: Wednesday, November 25, 2009 3:57 PM
  To: jim at almgt.com
  Cc: calvinlc at earthlink.net; roortube at gmail.com; s-car-list at audifans.com
  Subject: Stumbling under acceleration.....probable boost leak? Or...

  Seems to be the bane of late - please let us knjow what you nail down as a
specific culprit.

  Agree with the coil pack probablility, but look for boost leak too!


  {Date: Tue, 24 Nov 2009 21:42:24 -0700
  From: "Calvin Craig" <calvinlc at earthlink.net>
  Subject: Re: [s-cars] Stumbling under acceleration.....probable boost
  To: "Jim Fleischer" <jim at almgt.com>,<s-car-list at audifans.com>


  My top contender would be a coil pack.


  -----Original Message-----
  [mailto:s-car-list-bounces at audifans.com]On Behalf Of Jim Fleischer
  Sent: Monday, November 23, 2009 6:37 PM
  To: s-car-list at audifans.com
  Subject: [s-cars] Stumbling under acceleration.....probable boost leak?

  Hey guys,

  Just returned from a 900 mile mostly highway trip from Texas to
Colorado....Noticed shortly after heading out that there was some
significant, albeit inconsistent stumbling upon acceleration.  Could
half-throttle it and keep it from happening in the lower gears, but fourth
and fifth suffered under harder acceleration at lower revs.  Checked all the
obvious places for a tear, and tightened up all hose clamps I could get to
easlily.....no difference.  Car still pulls pretty well at upper RPMs, but
not smoothly by any means.

  Was able to replicate this with more regularity as the trip went on, and
seems to have gotten worse as the altitude increased.  Was downright
difficult at 10,200ft in Leadville, CO.  Disconnected battery overnight to
reset ecu, etc. and found no difference today.

  My thought is a boost leak, but cannot see/find a tear, and revving the
motor in place does not put enough load on to make anything readily
apparent.  Before I start tearing off hoses, etc. anything else I could be

  Car is a 95 s6 avant and just turned 80K miles this trip.  Hoses, POS,
  all original.  Replaced spark plugs and wires @ 60K.  Checked spark plug
torque, all good.

  Any and all help appreciated!  Do not want to take this in to anyone if I
can help it.

  Best regards,

  Jim Fleischer
  '95 s6 avant
  '83 ur]

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