Caldina GT-T Water Temp

[TOYO-GT-T]

On the way home last night I noticed my water temp was fluctuating for a brief while, I have never seen this before.

The water temp never went over the half way mark, but it would go down as far as one 1/4 on the gauge and then climb back up to half.

In the end it was holding on half by the time I got home, but it was def fluctiating for a wee bit.

Does anyone have an idea why?

[strx7]

was it REALLY cold when you were driving? I have seen this in my surf when heading between rotorua and taupo on a really cold morning, the windows started to fog up all of a sudden and the coolant temp guage dropped approx 20 degrees very quickly. I put it down toa pocket of very cold air that I musta gone thru

[Mr Revhead]

gauge sensor is a common fault

[TOYO-GT-T]

was it REALLY cold when you were driving? I have seen this in my surf when heading between rotorua and taupo on a really cold morning, the windows started to fog up all of a sudden and the coolant temp guage dropped approx 20 degrees very quickly. I put it down toa pocket of very cold air that I musta gone thru

It was quite cold. No lower than 5 degrees.

I think I will get the gauge checked out , car is under warranty so possibly I won't have to pay.

In saying this I don't know how I can prove I have gauge problems if it's not happening at the time when the mechanic is checking the gauge......

[big_boy]

also its posable your thermastit is on its way out & may have been sticking

[79rolla]

iv had this happen on cold morning the gauge will be shoing nearly warm or somthing ten next time i cheack it its droped down to bout quter again befour going back up
i just asumed it was just the cold that was doing it

[fivebob]

Yes I'd guess cold doing it as well.

What happens is that the cylinder head warms up, then as the thermstat opens for the first time it get cold water and cools down rapidly. Thermostat closes, head warms up again, thermstat opens, water is a bit warmer this time so it doesn't cool down as much. Each time the thermostat opens the water coming is a a liitle bit warmer so there is less fluctuation in the temp until it barely detectable.

[sergei]

I had similar thing on my 3SGTE, first water temp gauge then oil pressure one. Scared the shit out of me.
Turned out that the spade type plugs where corroded and loose which created loose connection thus jumping needles.
Clean up, bending the springs in the clips and small cable ties solved the problem.