"Catman" > wrote in message
...
> GT wrote:
>> "TonyB" > wrote in message
>> ...
>>>>>>> The 156 computer is nowhere near as clever as that.
>>>>>> Spoilsport
>>>>> It won't work on mine though, so I agree, it's not a clever computer!
>>>> You have to hold down the - and + buttons together for quite a while
>>>> before it says 'reset'. You have the newer interior version, right?
>>>> With the silver facings and the computer in the middle, above the
>>>> radio?
>>> That's the one. I've tried holding the buttons in for over a minute and
>>> eventually
>>> the display reverts back to the INFO screen.
>>>
>>> By the way, what temp should show on the gauge?
>>> The handbook says the needle should be midway or vertical which
>>> corresponds to 90º, mine seems to be about 75º.
>>
>> I asked about this a year back - mine rarely reaches the 90 degree mark.
>> It normally sits around 75 too. Has done this for 8 years, since new! No
>> affect on performance or consumption! Only time it ever goes over 90 is
>> after a decent motorway stretch, then a traffic queue. The fans kick in
>> and you can actually watch the needle come back down.
>>
>> Mine is petrol 2.0 JTS though - did you say yours is diesel? Temps might
>> be different, I dunno - expert please...
>
> <expert>
> The operating temps are, AFAIK, pretty similar.
> The biggest issue with a stuck thermostat can be overheating (if it sticks
> fully or partially closed), or more commonly IME lack of warmth from the
> heater if it sticks open.
> </expert>

Mine is the latter - heater is never very warm.

> Just out of curiosity, how do you know it's having no effect on
> consumption or performance if it's don it since new?

Well I suppose I don't, but I figure that my mpg is normal for a 2.0 JTS
petrol: it averages mid 30s to 37mpg normally and managed to get 49.9mph on
a few hundred mile run once. This was a very boring drive (56-60 + motorway
all the way - Edinburgh to Derby and back).

> Again, IME it *can* affect both if it sticks wide open, cos the engine
> runs rich for longer while warming up.

I think mine warms up past the 'rich mix' stage, just not much warmer past
that.