what does the error code for a ford focus 2003 mean? PO128
Customer the code P0128 means that the engine is not as hot as it should be, this means the thermostat is stuck open.
I hope this helps, if you have any further questions do not hesitate to ask.
how do i fix it, do i need to replace the thermostat. I live in florida so temps here are always hot. Also i was told i needed to replace the coolant temperature sensor in Advance Auto???
Customer you do not need to replace the coolant temperature sensor. The engine temperature needs to get and stay around 190 degrees farenheit. The thermostat can stick open, and even in hot weather, the engine will only reach 160 - 170 degrees. This is why the code is being set.
To repair this concern, you need to replace the thermostat.
If I can be of any further assistance let me know.
Ford Senior Master Tech & ASE Master w/14 yrs exp. Served on Ford's Tech Review Panel