I am probably out of my depth here but, As cold dense air makes for
harder acceleration and better fuel flow,(cold fuel+cold air) my T3
Caravelle goes alot harder in these conditions. Cold air is always
more dense/thicker and cold fuel makes for better spark at compression.
I will add at this point that on any trip to the cold country it is
always better value to install a larger(or is it smaller?) thermostat
or at least shove some cardboard in front of radiator so as to gain
heating, Run a hotter spark plug or coil, of course this all depends
on alot of things.
I cant say i have had any car "stall out" due to cold weather and i
have lived in Bega through the winter months with a T3 Carvelle, and
in this case even in the coldest of nights/mornings the vehicle
always ran perfect. I dont think there are too many differences in the
T3 Syncro engine when compared to the T3 Caravelle, 2wd. Yes when it
is cold the vehicle runs cold but in no way has performance been
questioned.
I am wondering what sort of coolant and coolant mixture you may be
running? Is it possible that the system has an air lock through it? Is
it possible that u have a leaking cylinder head? If You remove the
temp sensor on the thermo does it may any difference to engine? Have U
removed the cat02 sensor and idle stabliser and taken readings of how
much carbon is in cat chamber? I am sorry but i know very little about
the running gear of Syncros as many here have observed but as for a T3
the tuning side is something i have been delving into with great
results so i cant see how really cold air hinders performance.
As for the "cowl flaps" i take myn off in summer and put them back on
in winter on my 89 T3 Caravelle Gl 2wd.
Andrew
--- In
Syncro_T3_Australia@yahoogroups.com, "Les Harris"
<leslieharris@...> wrote:
>
> Mark,
>
> The quick answer is that the thermostat isn't functioning properly.
It is probable that a little piece of gunk is preventing it from
closing fully, thus allowing a cold by-pass, which in turn gives you
the low reading.
>
> The engine does have aircraft type cowl flaps, but it is the
thermostat in this case.
>
> The ECU responds to engine temperatures and can cause improper
running can be caused when the engine is not reaching the correct
running temperature.
>
> Les
>
> PS: Sorry about the empty reply - too fast on the trigger finger!
>
> ----- Original Message -----
> From: markkofahl
> To: Syncro_T3_Australia@yahoogroups.com
> Sent: Tuesday, June 12, 2007 6:37 PM
> Subject: [Syncro_T3_Australia] Running Hot / Running Cold Hesitations
>
>
>
> On the Syncro Tour '07 many will remember our Syncro ran quite hot,
> and eventually shut down.
>
> The water temp sensor has been replaced.
>
> The Oxygen Sensor has now been replaced with the Bosch (exactly like
> Peter's). General running has been pretty good since this replacement.
>
> On our trip to the Snowy Mountains (pics coming soon) the vehicle ran
> really quite cold, with the temp gauge often in the white arc, and at
> one point below the white arc on a long downhill run at night.
>
> When indicating below the lower white arc, the symptoms of hesitation
> re-appeared. Definitely not developing as much power and the same
> sense of fuel starvation (may not be this in fact, but the sense of
> it) and likelihood of shutdown, just like when it is too hot, became
> apparent again. It only happened the one time.
>
> As the hesitations when hot have generally occured on hot days in slow
> conditions (less air cooling) and now when cold in fast conditions, it
> seems to me the vehicle is quite sensitive to the amount of airflow
> available.
>
> In aircraft, we have "cowl flaps" to control the amount of airflow
> over the boxer engine to maintain constant / consistent Cylinder Head
> Temperatures. A Syncro does not have this of course!
>
> My questions surround:
>
> - do you generally see large variations in temperature through the
> winter/summer months
> - is it possible to run the engine "too cool"
> - is there likely to be some sort of further thermostatic control of
> the water cooling system that could be inoperable, bearing in mind the
> replacement sensors above?
>
> Thanks
> Mark.
>
> PS - when it was too hot, symptoms were:
>
> - high OAT
> - low speed
> - radiator fan now on
> - hesitation under acceleration
> - eventual stop
> - switch off / switch on does not permit restart
> - restart possible after period of cooling
>
> I have not been able to re-test the hot conditions since replacing the
> O2 Sensor due to temperature and time constraints!
>