Boost

[Junk Mail Box]

Kenneth -

I spent the last 6 weeks sorting out my car that had been sitting for three 
years.  I got it running without too much trouble, but boost was a problem. 
Initially it skipped and stumbled toward high RPM at WOT, especially if the 
accelerator was not gradually engaged.  It got better, but never quite right 
and I could not get the boost I wanted.  I have 3 ECU's (stock, IA III and 
IA III+) that I swapped in an out during the diagnostic phase with various 
results.

The best action was to pressurize the system and listen for leaks.  Easy, 
straightforward and extremely rewarding.  I found that the oil filler cap 
would not hold pressure and the vacuum line to the fuel pressure regulator 
just prior to the injection rail had cracked and broken at the clamp.  Two 
easy fixes and the next test drive gave me 20-22 pounds of boost on the 
boost gauge (tied into the feed to the ECU) at WOT in 5th.

I agree with the pressure check crowd.  This is the third time that tests 
rendered useful results, especially for cars that have been sitting for a 
while.  If you have a VAG-COM you can also take a reading on block 9.  If 
greater than something like 151, then it indicates a possible vacuum leak. 
Just check the Bentley as those readings were from my memory vs. what is 
written in the manual.  If you don't have the manual let me know and I'll 
verify the written numbers.

Good luck.

Steve Janesick
Now with email of sandsjunk at bellsouth.net (Had to change after another site 
I used was hacked and my ole email was bounced excessively from the 200 20v 
List.)

----- Original Message ----- 
From: "Kenneth" <auditude at cox.net>
To: "200 20v List" <200q20v at audifans.com>
Sent: Thursday, April 10, 2014 7:09 PM
Subject: Re: Boost


> That's great info and a handy link.  My only point was that to rule out 
> the MFTS requires just one finger and one thumb.  No tools, tester parts, 
> and source for compressed air, etc.
>
> Since the 1.4-1.5 bar of boost is what the WG spring would provide, I 
> personally would suspect that the ECU is not adding any boost for some 
> reason, although yes a boost leak should be ruled out in the 
> troubleshooting process.
>
> I'm not saying to not check for a boost leak, but I am saying that I 
> personally wouldn't check that first since the MFTS check is easier.
>
> Kenneth
>
> ---- Mike Miller <mikemilr at blackfoot.net> wrote:
>> All you need to do to pressure check the intake is us something like in
>> the site below.
>>
>> http://www.blackfoot.net/~hlm5860/Tester.html
>>
>> --mike
>>
>> On 4/10/2014 3:30:39 PM, Kenneth (auditude at cox.net) wrote:
>>  > Nothing wrong with that advice, but it is much easier to unplug the
>> sensor
>>  > than it is to disassemble the intake and setup a pressure check.
>>  >
>>  > Kenneth
>>  >
>>  > ---- Kneale Brownson <kneale at coslink.net> wrote:
>>  > >
>>  > I'd start with a pressure check for boost leaks
>>  > >
>>  > > Sent from my iPhone
>>  > >
>>  > > > On Apr 10, 2014, at 3:11 PM, Kenneth <auditude at cox.net> wrote:
>>  > > >
>>  > > > Jay Kempf <jkempf at madriver.com> wrote:
>>  > > >>
>>  > > >> I can get about 1.4-1.5 barr of boost out of a possible stock
>> 1.7-1.8
>>  > > >> on the gauge. Last time it was like that I changed the freq
>> valve and it
>>  > > >> immediately responded. So I went and checked the freq valve and
>> with 12v
>>  > > >> I get immediate click and release and flow through in the right
>> legs. I
>>  > > >> also checked the vacuum lines to and from the freq valve and 
>> boost
>>  > > >> bypass valve and all the rubber parts around those components.
>> All is
>>  > > >> perfect and holding vacuum and pressure. Checked the line all
>> the way to
>>  > > >> the fuel pressure regulator and all is fine. I made all that
>> stuff new a
>>  > > >> while back. I do not have working cruise control so I need to 
>> check
>>  > > >> there for possible vacuum leaks I am more guessing electrical.
>> Seems
>>  > > >> jus
>>
> _______________________________________________
> 200q20v mailing list http://www.audifans.com/mailman/listinfo/200q20v
>
>
> -----
> No virus found in this message.
> Checked by AVG - www.avg.com
> Version: 2014.0.4355 / Virus Database: 3882/7329 - Release Date: 04/10/14
> 



-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 2014.0.4355 / Virus Database: 3882/7332 - Release Date: 04/11/14