I think my punto (1.2 2001) has had just about every problem. The other day the temperature gauge went to the top and the red light went on but when I kept going it went down and back to normal at the half way point, so I added some more water as it was just to say below the min point.
It has been doing it the last few days on and off and it judders when it starting along with white smoke out the exhaust and when I checked the water today it was basically empty again. While I was there I checked my plugs as a mate told me to check for rust and this is when I discovered someone had put the leads on wrong, I changed them to be correct but 3 of the 4 plugs already looked sooty.
Once changed the car seemed to run a tad smoother and juddering less but the temperature problem is still there. I'm guessing it's my head gasket but i'm just wondering if it could be anything else before I go through the hassle of replacing it.

Head gasket has probably gone -- a compression test would confirm.

But why did the car overheat in the first place?

Likely causes:

Radiator fan failed to turn on
Thermostat stuck shut
Failed water pump
Clogged up, generally fubar radiator and or cooling system
Low water level

Obviously, if you don't find the cause, the HG will just go again.

The leads are 1 and 4 to 1 coil pack
2 and 3 to the other
Stamped/embossed on the Coil pack holder will tell you what order they need to be in


Sooty plugs = Excess fuel
easily believe misfiring

Fingers has hit the nail on the head
There is a fault that cuases the HG to blow in the first place

With a New HG, its new belt and water pump anyway, new thermostat is a safe play but a blocked radiator will need some seriouse flushing

find the cause before repair

Ziggy

I agree with finding the cause of an overheating event but... it seems the hg can go on these cars without overheating. Mention a Punto around these parts and the first thing everyone says is headgasket. If the failures are caused by things like stats and pumps you'd think we'd have figured it out by now. I've a few under my belt with no signs of overheating or pump failure and running happily after 25k with no skimming and reused head bolts ?

I'm no expert. But overheating can be caused by many things besides mechanical failure. I see "water" mentioned several times with regard to the cooling system...
Using pure water is the best way to rust up the coolant galleries over time.
The Punto's also have a low volume cooling system so a leak will quickly cause overheat.
Time to do a full check, fix, flush top-up with proper 50/50 coolant once the problems are fixed AND a proper bleed... you have to keep on top of this stuff or any car will play up.