MONDEO temp sensor

or the plug has fallen off or corroded

engine cold it should have about 100,000 ohms resistance, fully hot about

3,000

100k cold,3k hot :-), ok will try take a look went i go visiting owner :) hmmm, if i cant get a imediat replacement, i could bodge in a red,red,red,gold and a 100k pot. sweet.

Temp gauge sender, and Coolant temp sensor (for ECU) are NOT one and the same on the mk1 or 2 Mondy.

If heater is not toasty after 5 mins from cold start on a run, then reaplace thermostat.

Tim..

Does the water in the expansion tank heat up? If not it's the thermostat. (had this on 2 Mondys now, both under 5 years old.)

heater is fine n hot.

it runs like its cold it seems. but water is as it should be, nice n hot.

yes, water pipes all up to temp after a few min's drive drive

If the CTS circuit is faulty (short or open) the ECU will substitute a 80deg C value (i.e. nearly hot) for it, but will NOT enter closed loop running, which will increase fuel consumption about 10%.

If your gauge is also not reading, then you have a separate fault with this.

Tim..