Not quite, all Ford ECU's from EEC 3 upwards have LOS and in the case of the CTS circuit being shorted or open circuit, the EC|U would set a default value for that particular sensor, which in this case would be one for an engine at 70 degrees.
So in the OP's case his sensor cannot be OC or SC, but somewhere in between which the ECU doesnt flag as being erroneous.
Tim..
Hi folks, I'm a total ASS, I couldn't find a mention of the CTS sensor in the HBOL (Ive since found it) so I looked on the net. What I found was a mention of a fiesta CTS sensor mounted on the thermostat housing and a picture of a CTS sensor off a Vauxhall which looked just like the sensor mounted on my thermostat housing. Based on this I tested the sensor on the thermostat housing and it was open circuit.(It should be, its the bloody fan switch)! I have since located the CTS sensor under the inlet manifold. It had a resistance of 65K when cold, bought a new one, it read 61K. I have fit the new one, although I dont think that is where my problem lies now. My next plan is to disconnect the ECU plug and meter the wiring through to the diagnostics plug. If I can get the FCR working I might have half a chance of finding the problem. I have had to abandon the Fiesta for now as the MOT is due on my Xantia. More sodding work to do. I'll get back onto the Fiesta by the weekend, weather permitting.
Cheers Folks,
Tony.
But would it then start from very cold?
Right.
Being a Ford CFi, not a cats chance in hell!!
If it was something else multipoint, then probably yes after prolonged cranking, though it may be prone to stalling and spluttering til warmed through abit.
Tim.
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