VE SS Overheating idling any help be grateful

[Skaa]

I havent driven this car much lately probably twice a month Id take it out the garage. Was driving around for about an hour running a few errands and she just overheated into the red n threw a coolant temp high warning while I was sitting in idle at some traffic lights. I got moving and the temperature came back to normal as to be expected.

Was no coolant missing when I let it cool down n took radiator cap off.
I did notice only the drivers side cooling fan was working even when the temperature climbed up again toward the red at idle the passenger side cooling fan never kicked in at all.

I let it cool back down
I started her up from cold, idled it for 10minutes no problems at all temp just stayed at normal,
I then drive a couple kms n pull over again to let it sit in idle another 10 minutes temperature still sat at normal,
I drive another few kms then stop n let it idle again and after a few minutes suddenly the temp gauge goes up into the red again

Iv got a Hi Flow thermostat in it probably be a few years old now
Anybody got any ideas as to whether I have a cooling fan issue with passenger side fan not kicking in or whether it just works at highway speeds not sure bout that 1
Or a thermostat sticking or faulty radiator cap I'm not too sure why its playing up n overheating on idling sometimes and not all the time I'm idling

 

[07GTS]

have a look on the engineering mode at the actual coolant temp and keep an eye on it, if its slowly getting higher then its ok but if the CTS is failing and it jumps higher like 2 or 5 or more deg at a time then it could just be the sensor at fault, but id look at the second fan also both fans should be on at 105-107 deg think first fan is on at 98 odd deg

 

[Skaa]

Thanks man il have a look at it too when Iv flushed everything out

 

[taptapindustries]

A quick video on changing the thermostat on the v8.

Hope this helps

 

[MYVESSV8]

go cap first, don't forget to bleed once flushed