I do a lot of stop and go driving with this Escort. After replacing the head gasket which we discussed in another recent thread, I thought the car was going to be fine. This problem might have been there all along, I'm not sure.

Sometimes the temperature gauge goes up to boiling. Yes I can hear it boiling but the fan didn't start. If I can get it moving a bit the gauge will come back down to normal which leads me to believe that the thermostat is ok. A few minutes later the temp might start to go back up. The fan might or might not start. The fan itself was replaced a couple months ago. When the engine approaches boiling it sounds like the idle speed is increasing. It doesn't have a tach.

It looks like there are two sensors on the thermostat housing. I'm assuming that I want to replace the one closest to the hose which Haynes says is the ECT sensor. Is there also a fan control module somewhere I need to look for?

Am I heading in the right direction?

 

After almost 3 months I'm happy to report that the cooling fan has been operating properly. I cleaned the electrical contacts at the sensor and haven't had any problems since. I love it when an issue has a simple solution.

 

Glad it was a simple fix..

Thanks for the update..