Temp Gauge

[Guest steve o]

Got a C3 1.4sx auto 2005 reg .temp gauge went up to 3 lights pritty quick. now only going up to 2 then somtimes dropping back to 1 or up 3 after a long time thenback to 2 or staying on 3 ,changed thermosat and engine temp sensor,no change .any ideas?

[paul.h]

There are 2 temp sensors, one on top of the head which does the gauge and starts the fan/high temp alarm and one at the side which just does a high temp alarm/starts the engine fan. Did you get all the air out ? I had a Saab once which jumped up and down on the gauge and that was a faulty new thermostat that I had installed.

 

Our 1.4sx petrol normally runs on 3 lights but in very cold weather may not get up to the third. Is the engine fan cutting in early before 3 lights are on ? Suggest using a code reader with live data to see the actual temperature from the sensor. When I did this, 2 lights about 70°C, 3 lights on from about 80 to above 96°C at which the fan cut in so would not go higher - so when the thermostat opens (starts 89, full open 101°C) there should be 3 lights on (feel the radiator top hose which will get hot when it opens).