I own a 2006 Ford ka with a Duratec engine. In the very cold weather about 4 weeks ago I started the vehicle and drove it about 200 yards when I noticed the temperature reading indicator on the dashboard was lit up red. I turned round and coaxed it back at low speed thinking it was probably frozen as I had not put ant antifreeze in it. when the weather warms up a little I checked for leaks (there was no obvious leaks) put in a quality antifreeze and topped up the oil.

I used the car to do a couple of short journeys and all seemed well.

I went on a longer journey involving dual carriageway driving and the temp light came on after about 7 miles driving, I dipped the clutch to slow down the engine as I was a bout to pull over. Being on a dual carriageway I could not stop immediately so decided to slow down to 30 miles an hour. I slowed down and the temp light went out, so I continued with my journey for a couple of more miles and the temp light came back on. I dipped the clutch and coasted for a while and the temp light went out.

If I use the car for up to about 40 miles an hour it seems to be ok but when I increase the speed of the vehicle the temp light comes on I dip the clutch and coast and it goes out.

The vehicle is not overheating and the heater is working very well, the fan comes on at the radiator and everything seems to be ok in the cooling system.

Can anyone give me a possible reason for this fault and a solution.

Thanks in advance.

Edited by tony croft on 18/12/2016 at 11:08