A couple of weeks ago I blew a heater hose and overheated. I replaced the hose and thermostat. I repalced the temp sensor when no temp regestered on the guage. That worked for a day or two and now it will not work at all when first run. Every now and then the sensor will work after the car has been sitting after it has been fully warmed and restarted. It is setting off a fuel mixture fault code because the computer is not getting the message that the car is warm. I have re-checked the connection at the sensor and it looks good. I don't want to drive it much because I understand that it is running rich. Any ideas? Thank you in advance.

Steve