Thermostat.

briggsy9, Sep 26, 12:45am
When I put my car over 70 kms.I noticed the temp quage dropping.and when I pulled over and idled the quage went back to normal.I had the same thing this morning.with the temp guage dropping at speed and going back to normal when I stop and idle.Is that the termostat playing up!.

nzeva, Sep 26, 12:55am
Looks normal.at speed more air through the radiator causes the motor to run a little cooler. More noticeable on cold days as the difference between ambient (outside) air temperature and the radiator water temperature is greater.

jmma, Sep 26, 1:16am
Isn't this what the themostat is there to stop, OP it would be worth getting the cooling system checked, what vehicle!

briggsy9, Sep 26, 1:20am
Yeah,I just popped out checked the radiator.its all good,but I might drop it into the radiator shop to be sure about this one

jmma, Sep 26, 1:22am
How long have you had the car and what make, model etc

johnf_456, Sep 26, 3:24am
Check the thermostat take it and put it in some very hot water and c if it opens.

jmma, Sep 26, 4:32am
Really hot water (o:
Need to know what temp it is opening at really.

jason18, Sep 26, 4:46am
I would replace it. If ya going to the trouble to check it then replace it. It sounds like its partially jammed open

andy61, Sep 26, 5:06am
Replace the thermostat.

jmma, Sep 26, 5:10am
Agreed, but it must be worth testing in really hot water (o:

unbeatabull, Sep 26, 6:18am
This. They only cost like $13. When we do them at work we just replace them as it works out cheaper for the customer then them paying for the labour to accurately test its operating range/temps etc!

unbeatabull, Sep 26, 6:20am
As for the original problem, good chance it is the thermostat. Could also have an air pocket in the system, or a faulty component. If thermostat doesn't fix the issue would pay to get the cooling system checked.

mantagsi, Sep 26, 7:08am
Have a look on the thermostat, sometimes the opening temperature is stamped in it. Some open at 75°, some 82° to name a couple, so thats how hot really hot needs to be. For the price of it, just bang a new one in, waste of time mucking about. Once it is out to be tested, for all the hassle you may as well replace it and chalk it up to preventative maintenance

johnf_456, Sep 26, 8:34am
Sure if its cheap but on some cars you would be surprised how much the thermostat is, so thats one thing you wouldn't want to change for the sake of it. Sure most of the time its cheap and I swap them out but with the price of some certain euro's hell! Sorry fiat salesman.

jason18, Sep 26, 7:26pm
But what if it stops working in two days time! Obviously there is a problem with the cooling system so I would change thermostat, Probably see if radiator is due to be rodded out and flush entire system. Altho I dont believe in doing things by halves.

motorboy2011, Sep 26, 7:50pm
your thermostat is not closing properly from the sounds of it.

briggsy9, Sep 26, 9:54pm
Thanks everyone.my lil ole Toyota is booked in this arvo to have the thermostat replaced at the local radiator shop and they will give the radiator a flush and a check as there was slight discolouration in the coolant .big thumbs up to Burnside Radiators ChCh for prompt and excellent service and you`s here as well for good advice :-)