Originally Posted by
pdfbt40
Not on a Focus or late Mondeo Blacktop Zetec engine it isn't tabetha (except the ST170 engine).
The 'thermistor' sensor is a probe about 5cm long. Its screwed into a dry pocket from the inlet manifold face above cylinder #1. Hence CHT.
At operating temperature, CH temperature is 10-15 degrees higher than coolant temperature. Also if you measure the voltage across the thermistor, you have to allow for the EEC-V PCM changing the bias resistor as temperature reaches ~90 degrees (IIRC).
Martin
yep thts right, removed mine when fitting my new inlet manifold to my FRS, and was surprised to see it was a dry pocket,
my scangauge reads around 95-110 through most driving conditions in the warmer weather, fans kick in at 112 on the scangauge, the zetec is a "hot" running engine, just the way it was designed,
i also have a SPA water temperature / Oil pressure gauge, the water temperature is measured from a sensor installed in the thermostat housing so is measuring actual coolant temperature, it read approx 10 degrees lower than the scangauge
