Erratic temperature gauge

[APB22860]

I noticed on my 4 mile trip home from work on Thursday that the temperature gauge was slow to move, in fact it did not seem to move at all in the first 2 miles. Drove my daughter to a nearby pub in the evening and the temperature gauge was off the scale when I arrived inn the car park and a warning came up on the dash saying there was coolant loss and to turn off the engine immediately. I lifted the bonnet and the radiator top hose was cool and when I undid the expansion tank cap there was no pressure and the coolant level was correct. The engine fan was on.
I waited for the fan to stop and started the car the temperature gauge was at 60 so I decided to drive home a trip of about 2 miles. During the trip the gauge went up to 120 degrees on 3 occasions but then in a matter of seconds went back to a normal range. When I got home the gauge was at 120 again. and the error message displayed and the engine fan on. I went for a drive yesterday and had similar problems.
Has anyone experienced these issues before? I was thinking it could be the thermostat but these I have read normally fail in the open position and if stuck closed would not explain why the gauge is behaving erratically. Could it be the water pump? It is not leaking or noisy. Otherwise a faulty sensor?

 

[zipdip]

My money would be on a faulty temp sensor,just make certain that the connection to it is tight,if it is then replacement is not that expensive,I am sure we had another member with a similar problem,does your car have the ability to show the actual temp on the dash,some cars do,by your actions in the pub car park you have proved the car was not overheating ,as the top hose was cold and the expansion tank was normal.

 

[Jamiewatkins2004]

I’d say faulty thermostat. Take it out and heat in a pan to see if it opens, if not then new thermostat required.


Sent from my iPhone using Tapatalk