I have an original 2001 PT Cruiser with 92K miles. For the past few years (yes, years) I occasionally see the temp go high enough to sound the alarm.
The system has been flushed, pressure checked, radiator cap replaced. When this occurs reving the engine up to about 2K brings it back down to normal but if let to idle it will rise again.
This willl usually occur after a hiway speed drive then coming to a stop. But not always. Actually very in frequently.
I even have the factory shop manuals and have done what it suggests to no avail.
Might anyone have any ideas wihy this particular 2.4L motor does this?