Temperature sensors

[Revon]

97 chimaera, serpentine engine
My temperature gauge has recently stopped working, but prior to that the fuel consumption has worsened significantly. I intend to replace the ECU coolant temperature sensor (recommended by many as first step for fuelling probs), but does this sensor also feed the temperature gauge? Many threads suggest there is a second temperature sensor for the gauge located just behind the ECU temp sensor. Mine has this sensor, but has never had anything connected to it. Does the ECU (or another amplifier) generate a temperature signal for the gauge, or is there another sensor hidden away on the engine?
There is no change on the gauge when I disconnect the ECU sensor (reads about 55-60 degrees)
Also any idea where the wiring goes from the gauge - I can't trace it back by colour to ECU or engine.
thanks in advance

[shpub]

Gauge and ECU sensor are totally independent. The guage one is usually behind the distributor.. There is another on the engine by the ECU one but this is normally noty used. It is possible that the guage is connected to this. It's the wrong sensor but can be made to work with a resistor so that it is approximate.

>> Edited by shpub on Sunday 22 January 13:28

[Revon]

Thanks for that info, found the sensor, and its even same colour wire as the one going to the gauge! Looks like a bugger to replace though.

[david beer]

I use the spare sender(and many, many others), have done for years. The original is hardly accurate(cold readings), so the spare is a lot easier than draining water, skinning hands etc. For a10p resistor (120 ohm usually), got to be the way to go. Variable resistor would be favourate though, only a few pence more.

[the jiffle king]

Quick question about this.

My temp gague is not working and I have replaced the ECU temp sensor, and checked coolant levels to make sure there is some coolant to touch the sensor.

Where would I get one of the resistors? and how easy is it to replace it.

Thanks

T-J-K