Citroen Xsara Picasso Overheating

[pioneer1963]

Good Afternoon,
I have an intermittent fault on my xsara picasso 1.8 Petrol 2001 100K mileage. Over the last 2 weeks a message has come up on the dashboard screen advising to stop driving as engine overheating. The thermometer is at max at this time.I pull over and can hear the fan in overdrive. This has happened twice over the last fortnight.The coolant level is at max.Over the years the thermometer has been at 2 notches when driving but i notice now when engine is not overheating that the thermometer sometimes stays at zero. Any ideas on what could be causing this and whether its something that be rectified without needing any special tools, thanks for any help

 

[Burnerman]

I think initially you have to check out the condition of the thermostat - this is designed to keep the engine at a constant 90 degrees C.
If it won't open fully, or is spasmodic in its operation, overheating is the result.
The operation of the thermostat is directly connected to the temperature gauge readings......if the gauge reads zero then the thermostat hasn't opened (yet!)
John

 

[pioneer1963]

Thanks John, do you know if the location of the thermostat is easily accessible on this car

 

[Burnerman]

As far as I know - as I've only come across the diesel Picasso, the thermostat is in a housing near the top of the engine. Follow the top radiator hose back and thats where it is likely to be.
These engines often have air bleeds too - at the top of the rad, at the heater radiator top hose and maybe the thermostat housing itself are likely areas.
If you can, when the engine is fully warm, feel the radiator core to see that it is warm all over - but do watch out for that electric fan!
John