turbo coolant hose under the PS pump [now heater valve]

[Kenneth Keith]

On 8/29/05, Bernie Benz <b.benz at charter.net> wrote:
> 
> > From: Kenneth Keith <auditude at gmail.com>
> <Snip>
> > The same failure happened back in the day on my '88 5kcstq.  Now I
> > need a new heater valve.  There is an all-metal one that I found at
> > Napa, here:
> >
> > http://www.napaonline.com/cgi-bin/ncommerce3/ExecMacro/NAPAonline/search_resul
> > ts_product_detail.d2w/report?prrfnbr=15568088&prmenbr=5806&usrcommgrpid=629505
> > 94
> > .
> > That one doesn't have what appears to be a water temperature sensor in
> > it, which my originals had.  I do like the all-metal construction of
> > that Napa piece, but do I need to get the factory plastic one with the
> > temp sensor in it?
>
> Bentley is in error in that they label both this DCC (digital climate
> control) WTS (water temperature sensor) and the ECU WTS as being G62.  Makes
> trouble shooting very confusing!  They may well be identical sensors, not
> enough T/R info on the ECU WTS to be able to tell for sure.  But the two
> circuits have nothing in common.
> 
> The DCC WTS' only purpose is to shut off the hot water flow to the heater
> core when not needed, so it could be located anywhere, and was not used on
> some earlier models, hot water being on all the time.
> 
> Hope this helps, Improvise!
> 
> Bernie

Hi Bernie,

Thanks for the response.  That system does seems a little ambiguous. 
I was told by my Audi dealer shop foreman friend of mine that the MFTS
is what is used to measure coolant temp for the climate control
system.  So, it sounds like I can use the all-metal style without the
sensor.  Actually, I will maybe test this out and unplug my sensor and
see what happens.  The heater valve sensor function is redundant to
the heater flap anyway, right?

I find it almost amazing that they haven't superceded that ridiculous
plastic valve with something else.  If it had dumped while on the road
or something, it could have been really bad.  Granted, it is a 15 year
old part on an almost 200k mile car, and it should have been inspected
and/or replaced on a schedule, but still!  =)

Thanks,

Ken