[urq] Re. Warm-up regulator questions

Ben Swann benswann at verizon.net
Sun Sep 7 16:37:58 PDT 2008

The WUR is often one of those things that may or may not neeed attention and you won't
know until you open it up.  Running fuel pressure tests before doing that may give a
clue as to if it is operation correctly.

I have a few I rebuilt and they did operate in range after that, although problems I had
ended up being related to something else although I did find some debris in both.
Usually there would be a tiny bit of crud that can be carefully cleaned out.  I've had a
few that required a little 1000 grit paper to polish off a little rust area on the
diaphragm. Disassemble and reassemble with methodical care.

There are two ports on the UrQ WUR and they can likely be used differently than the
stock application to provide additional enrichment on boost, but I found that to be
unecessary. I did think it strange how since the two port counteracted each other that
both wer tee'd into the same manifold pressure port.  What I found in testing is one
port I think the one that enleans is about 3X the force of the one that enrichens, but
forget and it may be the other way around.  So, basically works per design OK when all
is operating normally.  The thermo-time switch/valve opens when warming up - AFAIRC and
puts the warmup circuit operating to enlean.

I'd have to check my notes I scribbled on the factory training printout I made to see if
what I said is backwards, but basically you can take them apart carefully and see how
they work when cleaning - just be methodical.  If you find rust, things may be beyond a
basic cleaning, but may still be worthwhile to try.

LMK if you need one, as I no longer use mine since I converted to EFI.  I'd like to keep
one for the complete engine I have been trying to sell, but still have a completely good
one in addition.  I've been trying to keep all that together as a package, but probably
I'd get more for the WUR and a few other parts than what I'm asking for the engine -
hint hint.



[Date: Sat, 6 Sep 2008 16:38:08 -0400
From: "Louis-Alain Richard" <laraa at sympatico.ca>
Subject: Warm-up regulator questions
To: "Urq" <urq at audifans.com>,	"Brady Moffatt" <info at dynodoc.ca>
Cc: quattro at audifans.com
Message-ID: <BLU0-SMTP9D860B6FEECC357B49738CE5B0 at phx.gbl>
Content-Type: text/plain;	charset="us-ascii"

Hi everyone,


My freshly rebuilt stock WX is experiencing a rough idle during the warm-up phase. It
starts very easily, hot or cold, but during the first 30 seconds when cold I must help
it survive with the gas pedal. My understanding is the WUR is bad or dirty. I've swapped
it for another one I have, same result.
Both WUR electrical parts are OK, showing continuity when tested. When hot, the engine
is fine with a nice air-fuel ratio on the rich side. The urQ WUR part number is 0 438
140 094 or 035 133 403D.


Before I open one of them, I have a few preliminary questions :

1-       There are two vacuum ports on them, and both ports are connected
together via tubing and a T-piece and the other part of this T is connected to the
thermo-vacuum switch. Is this right ?

2-       Is the thermo-vacuum switch supposed to be closed or opened when cold ?

3-       Is there a good way and a wrong way of connecting that switch ? Or is it only a
valve allowing some vacuum/boost to reach the WUR when cold/hot ?

4-       Anyone had opened a WUR before for cleaning purposes ?

A new WUR is a 500$+ affair, so I've looked other solutions if I must replace it. Look
at these guys, they propose a variable pressure WUR which one tunes via a laptop. It
looks very interesting, but price for a turbo engine WUR is 600$.Ouch! 


Look for the UTCIS-PT, that's the one for turbo engines.


Brady, could this be a nice thing for tuning a CIS lightly modded engine ?



Oh btw, we have another baby girl in the house, lil' Simone. She's born on august 24th,
and the baby and the mother are both going very well. When I got the other girl in 2005,
Estelle, the very knowledgeable Brady Moffatt told me there was a car of that name, the
Skoda Estelle. In fact, it was the UK-only model name for the rear-engined communist-era
pre-VW Czech econobox.
Since they were also sold in Canada during the 80's, albeit under the Skoda Rapide
moniker, I am seeking one survivor on which I will affix the UK badges, hence lil'
Estelle will have an eponym car for her prom night in 2021. Now, I need your help to
find an appropriate ride for Simone : the Brady-pedia was clueless about any car of that
name, but I am sure you guys will find me an obscure version of a forgotten car that I
will have to get for the other one prom night in 2024.


Thanks in advance,



1983 Quattro]

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