On the 323 1.6L SOHC engine, the thermostat inserts directly into the head. Over the thermostat, you place the thermostat housing cover. In the thermostat housing cover, there is a sensor.

I thought that sensor was called the Coolant Temperature Sensor or CTS, but apparently, that refers to a sensor in the radiator itself? Anyone know what it's really called?

I busted it when I replaced my thermostat a month ago. It's finally given up the ghost, and I've heard that you can really screw up your gas mileage if it isn't working properly. Tried the parts store today - they produced what they thought was the part, but it doesn't fit the thermostat housing (part they had was too small).

This picture is not of my particular thermostat housing cover, but it is equivalent. The name of the sensor in the cover is what I'm looking for.


[IMG]local://upfiles/15322/9FA3CC64E1A5456B8C675511968CA0FC.jpg[/IMG]

 

Ok, I think I got an ID. It is a Coolant Temperature Sensor, but it is one of two on this particular engine. The other one is buried somewhere in the radiator. Most auto parts stores have the one for the radiator, but do not stock the one in the thermostat housing cover.

I think that's the case. Anyone got anything else?

 

Just an educated guess, but the one in the rad probably only controls the electric fan. This is pretty typical.
The one you need may (or may not) be the one for the gauge in the cockpit.