Warm-up regulator questions

Louis-Alain Richard laraa at sympatico.ca
Sat Sep 6 13:38:08 PDT 2008

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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