Changing the temp sensor was just a wild guess. It obviously was not the problem. You need to get the codes read to find out what's really wrong. The places that read codes free CANNOT read the codes you need. Take it to either a good independent shop or a Ford dealer.
The codes stay in memory for about a month after the last time the light flashed, so don't let them tell you the light has to be flashing to read the codes.
The codes stay in memory for about a month after the last time the light flashed, so don't let them tell you the light has to be flashing to read the codes.