(T) Crazy temperature gugue

I have just started having trouble with the temperature gague on my Mk2 Sporting Punto. Typically, I drive along for 5/10 mins and the temperature guage does not move from it's resting point. Then, it suddenly goes up to the normal position (where it has always been since new). All is well for a while and then it suddenly shoots up to the top and the red warning light comes on. It's then up and down like a yoyo for the rest of the journey. The temperature gague CAN'T be displaying the correct coolant temperature as the fluctuations could not occur that quickly. It doesn't go up in stationary traffic or when parked up.

There is now water leaking from the radiator, the water levels are fine, there is no 'mayo' round the filler cap. The heating inside the car works perfectly and the car runs fine and is not overheating.

Any ideas? Dodgy temperature sender??

i would say check the connection on the sender 1st before replacing it. could just be loose/dirty

sounds a bit like a knackared voltage regualator in the instrument cluster, you really need to eliminate the sensor and wiring before you touch that tho.

Thanks for the suggestions...

Sounds like a really divvy question, but where abouts is the temperature sender located so that I can check to see if it's dirty/loose?

T

Just been to FIAT Cwmbran. They have had a quick look and it appears that tthe thermostat may be sticking and I have air in the system. This would account for the wild fluctuations in temperature that the sensor is sending to the termperature gague. It would also explain the gurgling sound when revving the engine. Booked in to be fixed next week.