As per the title, I was driving along today and after about 25 minutes had the temp gauge shoot up to the red and the warning about overheating display. I turned up the heater to check the temp and it was blowing hot and as I did so the temp gauge started to fall back to the 90 degree mark. I pulled over and checked the coolant level and the oil as well for signs of coolant contamination, but everything was normal, also no leaks were visible from under the car. Restarted the car and within 2 minutes same again the temp gauge headed towards the red, this time I switched the heater fan on full and the temp dropped back to 90 degrees. 

I turned the fan down after a couple of minutes and everything was ok for the rest of the journey, which was just over 2 hours of mainly motorway at 70 mph, with 20 minutes towards the end of stop start traffic. Is there a known fault that would cause this, on searching I've seen a problem with Octavias but cant find anything with the superb. Its a 2016 2.0 td 150 L&K.

 

Thanks in advance 

sorry could one of the mods please move this to the mk3 forum, Thanks