Hello I have got a 2000 W reg Mondeo which has never shown any faults with the temperature gauge before, and indeed the car runs cool at 1/4 of the way up the dial and rarely moves from there in the 5 years ive had the car.

However today I noticed the temp gauge needle moving slightly, like it was dancing a slight bit left and right, the temp didn't change but the needle was moving slightly left and right.

Any idea what might be causing this please so I can try and rectify it early?

Coolant level is at max and has not been topped up in 1 year (has not needed to).

 

Thank you.

Might be the sensor on the way out.

2 hours ago, pragmatix said:

Might be the sensor on the way out.

Is that expensive or easy for a garage to fix?

Any other options it might be cos I know these types of things could be a 'try this' and 'try that' type thing sometimes.

Airlock in the system or duff thermostat?
When is the coolant due a change?

Sent from my SM-G965F (S9+)

Last had the coolant changed 18 months ago when I had a new radiator fited, as the levels were stable and I only do 4k a year I havnt renewed it since.

Check the levels and then warm the car up with the coolant cap off to allow any trapped air to burp out.
Don't warm it too far though to avoid splashing hot coolant on the engine bay or yourself.

Sent from my SM-G965F (S9+)