Xantia Temp (again...)

manic_man · Post by **manic_man** » 12 Mar 2004, 01:09

lol, sorry, ive seen this a few times recently, but nothing has really answered my question yet, so im posting my own :p
Got a 1997 Xantia TD on 87k. Had it for around 4 months now i think. Newho, how long should it take to warm up when its pretty cold outside? (prolly windchill of around zero) in a 5 minute run its up to around 60, if i let it idle for say another 5 mins it'll get to around 65.
for longer jourmeys, it usually makes it to 70 pretty steady after around say 10 minutes from cold. never really see it go above 80, mebbe just slightly above when nearly doing a tonne down the old autobahn (no really...)
newho, ive seen ppl saying an optimal operating temp of around 80 is correct for the xantia.. well my "operating temp" seems to be 70.. as thats what its on most of the time

Now the reason for my confusion: ppl have been saying the xantia's with A/C is correct?
So i ask you, is it running cold... do i need a new thermostat? Or is it fine?

Richard Gallagher · Post by **Richard Gallagher** » 12 Mar 2004, 01:21

It would appear that a new thermostat is required, it should be around 80 irrespective of whether A/C is fitted.
The only differnce A/C makes is that because the cooling fans are running almost constantly the temperature will not increase unless its a very hot day as per last summer. Boy does that seem a long time ago now!!

andycarter · Post by **andycarter** » 12 Mar 2004, 01:41

I think I've seen several threads about 1.9TD Xantias with a/c running @ 70°C. Well so's mine!
I imagine there's a 'me too' factor involved with all these posts so how about the possibility that citroen got a whole batch of thermostats/senders/gauges that were wrongly calibrated aroung 1996/1997 (?) Or maybe it's just an undocumented design feature!
Before I get too paranoid and go changing the thermostat I'd like to measure the temperature in a few places by another means to see if its just the gauge reading low.
And if it really is running at 70, why should we rush out and change our thermoststats? Anybody actually found some benefit by running at 80?

Richard Gallagher · Post by **Richard Gallagher** » 12 Mar 2004, 02:08

Lower fuel consumption and a warmer heater, very relevant today! What I normally look for in the absence of thermometers for testing etc is to put the heater on hot with the engine at its normal running temperature and feel the heater temp output. If running correctly, it will normally have some 'bite' to the heater making it uncomfortable to leave your hand there for too long.
Not scientific, but no extra equipment required and a rather cheap method of testing.....

andycarter · Post by **andycarter** » 12 Mar 2004, 02:20

Richard -
Actually I've no complaints about the heater, it seems to get up to temperature within about 1/2 a mile.
Fuel consumption is usually only 40-45 mpg (mostly A-roads / 25 miles each way daily commute) I'd be much happier with 50 mpg though[;)]
Have you had to replace your stat, and can you quantify any improvement in mpg?
Andy

Richard Gallagher · Post by **Richard Gallagher** » 12 Mar 2004, 02:53

My present Xantia has only done 28,000 miles, I've had it from new and the temperature has always been a 'gauge needle width' below 80 degrees (78/79?) when running normally. A previous 1995 SX TD (also bought new) would read 80/81 degrees.
I've found with cars that after they get to 50,000+ miles the thermostat is inclined to open early, thereby not allowing the engine to reach its designed operating temperature which can have an effect on enconomy due to 'cold start devices' closing later or not at all. i.e. the choke stays on.

manic_man · Post by **manic_man** » 12 Mar 2004, 05:55

hmm, well i have absolutely no complaints about my heater temperature... i can pretty much burn all the occupants of my car with the heater whacked on full

in terms of economy... i dont have a clue.. but i tootle around on a tenner for a couple of a weeks at a time (not vast mileage

)
Its gonna be serviced in the next few months, so i'll get it looked at then, can any damage be caused by a possible sticky thermostat?
I just hope its not a sign of the head gasket going or nething... i cant afford 2 spend ne excessive money on it atm :s

Stempy · Post by **Stempy** » 12 Mar 2004, 12:37

My Xantia V6 is suffering from running too cool and all clues point to a faulty 'stat. It takes forever to warm up and cabin temperature never really get hot enough unless you are sitting in traffic at idle. It seems to run much smoother if it has been idling for a while and allowed to get to a good running temperature, but as soon as you get any speed up the needle drops right down to below 70. It even affects the gearchange pattern.
I've tried feeling the radiator from cold which just slowly gets warmer rather than the sudden surge of heat you might expect from an opening 'stat. I even got it hooked up to a diagnostic machine which says it's running 12ºC below optimum.
IFAIK the only things that can control the engine temperature are the 'stat and the cooling fans, I don't think there's any electronic jiggery pokery that has any effect.

Post by **RichardW** » 12 Mar 2004, 12:51

The actual temperature on the gauge is not so important (given the vaugaries that are associated with it) - what is more important is the behaviour. If the stat is working OK then the temp should rise reasonably quickly to an operating temperature, and it should then stay there regardless of speed / heater operation etc. It will rise if sat in traffic or if working the engine hard, but should soon come down again when the fans come on or you start moving again. Once at operating temp it should never drop. If the temp gauge is dancing about all over the place in normal running then the stat is shot.

andycarter · Post by **andycarter** » 12 Mar 2004, 14:14

Just this morning I arrived at work, left engine running and put a thermometer on a few places around the engine.
Highest reading I could get was at the base of one of the injectors (68°) Ambient temp was er, well it was snowing.
Also I tried the suggestion of Richard Gallagher with the heater on full whack, it was neither unbearable nor did it exhibit any 'bite' but then it was pretty cool outside so I'd expect the heater to have a tough time raising the incoming air temp by that much.
Maybe I will change the stat... let you know if mpg does improve[:p]