This is my commuter car and still hanging in there with 222k now. About a year ago it started getting pretty hot at idle...and def easier to reproduce in warm weather.

Never had issue at speed only stop and go or idle. AC fan will engage if i turn that on. Normally temp stays a bit below half... But if idling even for maybe five minutes yest as an example temp starts to creep. Once it starts it moves quickly from maybe 40% to about 90% of the way to hot in maybe three minutes. At that point radiator fan will kick on and drop. Water pump replaced maybe 50k ago. Coolant levels are fine.

No antifreeze in oil... I dont think its a head gasket. Any best guesses here? Radiator replaced 3-4 years ago as well.

Thx

 

Actually just checked the levels... Overflow tank between min and max when cold but radiator was low... Added maybe 350ml to top it off.

Also ran for a few min w/o cap and there was no bubbling.

 

Used an engine block tester today to check for CO2... Stayed completely blue the entire time...zero change.