Avant stalling

[Peter Schulz]

Guys:

According to the 200q20v service training manual, and the excerpt on Chris 
Miller's website:
  a faulty or improperly adjusted idle switch (integral part of the 
Throttle position sensor) will prevent correct ISV operation.

The throttle Position Sensor  (TPS)is mounted to the throttle body by some 
small screws, and since the holes on the TPS are slotted, its position with 
respect to the throttle body CAN be adjusted.

So make sure that you get an audible <click> when the Throttle is in the 
"idle" position - if not, first try adjusting the TPS position.

-Peter

At 12:21 PM 3/12/2004, Ingo D. Rautenberg wrote:
>Brandon,
>
>Generally speaking, ISV failure on 3B motors is pretty rare (though their
>relatively low production number may partly explain that).  A spirited run
>with a defective bypass valve or plumbing followed by a rapid slow down to a
>stop and stalled out engine is usually indicative of a faulty BPV IME.  Do
>not overlook the small diameter hose from the BPV to the back of the intake
>manifold -- original ones tend to deteriorate and so I suggest replacing
>with silicone tubing available from various sources (I have red from WMB
>dealer).
>
>Simple check on whether or not the ISV is functioning properly would be
>simply to unplug it and see if there is any change in idle or stalling.
>
>HTH
>
>-Ingo
>
>----- Original Message -----
>From: "Brandon Rogers" <brogers at terrix.com>
>To: "200 20V List" <200q20V at audifans.com>
>Sent: Friday, March 12, 2004 11:46 AM
>Subject: Re: Avant stalling
>
>
>I'm still not totally clear which symptoms point to BPV failure vs ISV
>failure.
>
>Any help appreciated.
>
>TIA-
>
>Brandon
>
>   ----- Original Message -----
>   From: Ben Swann
>   To: Brandon Rogers
>   Cc: TM ; 20020v at spymac.com ; 200q20v at audifans.com
>   Sent: Friday, March 12, 2004 9:40 AM
>   Subject: RE: Avant stalling
>
>
>   I have not had any problems with my stock bypass and am running 2.5 bar
>boost.
>
>   I had the problem as you describe and it was remedied by repair/replace
>the Idle Stabilizer Valve.
>
>   I sa r/r because I cleaned the original ISV once and the problem resolved
>for a time.  Cleaned it with throttle body cleaner.  Eventually I had to
>replace it, and the  problem has not recurred.
>
>   You may want to verify operation of both, or at least BPV since this is
>the easier to test, before replacing anything.
>
>   Ben
>
>   [Date: Thu, 11 Mar 2004 12:41:01 -0500
>   From: "TM" <t44tq at mindspring.com>
>   Subject: RE: Avant stalling
>   To: "'Brandon Rogers'" <brogers at terrix.com>, <20020v at spymac.com>,
>   <200q20v at audifans.com>
>   Message-ID: <002d01c40790$06318450$0400a8c0 at TAKA1>
>   Content-Type: text/plain; charset="US-ASCII"
>
>   Typical bypass valve failure creates the exact symptoms you describe-
>   I've had two stock valves fail on me- the engine stalls when you cut
>   the throttle and coast to a stop. Replacement of the valve fixed it
>   every
>   time. I'm running a Bailey, no problems since.
>
>   Taka
>
>   -----Original Message-----
>   From: Brandon Rogers [mailto:brogers at terrix.com]
>   Sent: Thursday, March 11, 2004 12:35 PM
>   To: TM; 20020v at spymac.com; 200q20v at audifans.com
>   Subject: Re: Avant stalling
>
>
>   OK-why does it seem like the BPV, not the ISV?  Is it because the clutch
>   is engaged and failing BPV causes compressor stall..then engine stall?
>   And symptoms of a ISV failure would be pushing in the clutch and engine
>   stalling instead of falling to idle?
>
>   Thanks for the edumacatin'
>
>   Brandon]
>
>_______________________________________________
>200q20v mailing list
>200q20v at audifans.com
>http://www.audifans.com/mailman/listinfo/200q20v
>
>
>
>---
>Outgoing mail is certified Virus Free.
>Checked by AVG anti-virus system (http://www.grisoft.com).
>Version: 6.0.615 / Virus Database: 394 - Release Date: 3/8/2004
>
>_______________________________________________
>200q20v mailing list
>200q20v at audifans.com
>http://www.audifans.com/mailman/listinfo/200q20v


Peter Schulz
1990 CQ (perpetually awaiting S2 3b engine transplant)
1991 200 20v TQW indigo mica
1991 200 20v TQW titanium grey
Chelmsford, MA USA
peter at audifans.com