Hi everyone is it usual for the temp gauge to appear to be really cool whilst driving but rapidly rises in traffic etc ? The heater works and the fan kicks in once past half way, it’s a very low mileage car and I’ve had the belts etc done recently, but the garage didn’t replace the thermostat, is this normal ?
Thanks
Shaun

Yes, that's normal. When you are driving normally there is a flow of air through the radiator which keeps the temperature constant. Once you stop, or are in slow traffic, that airflow stops and the temperature immediately begins to rise until the fan cuts in creating airflow through the radiator again. Provided the fan is kicking in, which you state it is, then everything is ok. You do need to keep a check your coolant level though, as the switch for the fan is mounted quite high up on the radiator and if you let the level fall too much it may not trigger the fan.


A quick word of advice with the 1.6 is to place the ECU in a plastic bag. The reason for this is that it is mounted directly beneath the heater matrix behind the centre console. When your matrix develops a leak (not if, but when), it will leak onto your ECU destroying it. A plastic bag will keep it dry.

That’s great thanks will do that ASAP

My winter drive around is an old RAV4 and the temp gauge never fluctuates from just under half way no matter what, with the punto doing this I’ve been getting a fair bit of anxiety at the rate it rises when in traffic or lights

it sounds pretty normal but when you say it runs really cool when driving along, how cool?

I think I would be more worried by a temperature gauge which never moves than one which tells you what is going on. I also own a Jaguar XK8 which has a temperature gauge which behaves like your Rav 4 and many owners have replaced the gauge with a more responsive and accurate gauge which does fluctuate as the big alloy V8 doesn't like overheating!


As a guide for what blu73 asked, my gauge usually sits just below the halfway mark in when moving in free air.

yeah i was just thinking the stat might be sticking a bit and not fully closing - this would result in the car taking an age to warm up compared to whats normal and the temp dropping lower than it should whilst going along. But I agree, temp gauges on alot of cars, particularly newer cars seem to just go to the middle of the gauge and stay there all the time when clearly the temp of the engine does go up and down. Read loads of times people getting into fiats of this kind of age and then worrying the temp doesnt just stay one temp but thats totally normal.

Hi guys the gauge is barely a quarter up whilst moving along, but traffic build up soon has it rising to more than half when fan kicks in very briefly

in that case i'm gonna guess the thermostat is stuck partially open - which is a pain but hey, at least it didn't stick shut... Sounds like its too cool when moving and getting hot faster than it should idling.

Yep think it’s time for a new thermostat just in case