Recently my 1988 Mk1 Uno fire (999cc) engine seems to be remaining 'cold'. The engine temperature usually goes up to or almost up to 90 degrees C (as should be). However it is recently finding it difficult to even get up to the first quarter.

It is also important to mention that here in Malta we are recently having bad storms and weather much colder than usual (6-8 degrees C). Could that be the reason? And is it normal for a 999cc uno to remain 'cold' in colder countries?

Driving home this evening (in the storm) with wind, hail, lots of water and what not, the temperature idled at 50 degrees C.

My money's on a stuck open thermostat. My panda does the same thing. If I leave it stationary long enough It will reach 90 but driving around it's always about 60 degrees. Just one of those jobs I'm putting off till the spring.

I've got the thermostat changed. Taught it was that to be honest. However it still doesn't go up to 90 when driving. It's just above the first quarter. Better than before. And heats up much quicker!

I too have the same issue. Mine is a 999cc FIRE and I've replaced the thermostat twice. The temp gauge needle reads just under 90 (around 80 mark??), but will reach 90 if idling in traffic excessively. I think they are just like that. Besides hoe accurate is the temp gauge?
I noticed that the BEHR brand thermostats are in the stuck open position when I removed them. Probably manufactured faultily from the start.