harrisyork
New Member
2017 EL Limited 4WD w/HD towing package.
I have a P0128 code issue
Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
BUT--before you tell me to change the thermostat let me outline what all I have done so far and where this all started.(Since temp is the issue at hand, I will tell you I live in Georgia)
-Radiator Fan blows like a Jet engine(i've read all over, people say its normal, but i think it shouldn't be)
-Car "overheated" often, not regularly, but often(especially in summer, not really ever in winter)
---I verified the temp numbers on OBD2 scanner, regularly at 220F+, sometimes up to 240 in summer
-Changed thermostat, motorcraft RT1255(little if any changes)
-Changed CHT temp Sensor(9L8Z-6G004-E)
-VOILA!!! Fixed, NO overtemping, no high running fan. Temp numbers verified on OBD2 again.
-BUT----Less than 100 miles later, P0128 code. (I think whats the big deal, but obviously car doesn't like it)
-I test the temp numbers of the Thermostat housing using an Infrared thermometer and they are the same as the CHT temps sensor numbers.(so I assume I have an actual under temp condition now).
-Car now takes a good 30-45 minutes to warm up to the 190 thermostat temp. Eventually gets there, but even in this cooler weather will cool down on drives as much as 160 degrees.
-SO, I pull the thermostat and test it in boiling water with a temperature gauge in the water and it works as advertised. Opens slowly around 185 degrees. So no Thermostat problem?
WHERE DO I GO NEXT? My only play at this point is to try another thermostat, but I want to pick other people's brains before I go changing something that I just replaced.
I have a P0128 code issue
Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
BUT--before you tell me to change the thermostat let me outline what all I have done so far and where this all started.(Since temp is the issue at hand, I will tell you I live in Georgia)
-Radiator Fan blows like a Jet engine(i've read all over, people say its normal, but i think it shouldn't be)
-Car "overheated" often, not regularly, but often(especially in summer, not really ever in winter)
---I verified the temp numbers on OBD2 scanner, regularly at 220F+, sometimes up to 240 in summer
-Changed thermostat, motorcraft RT1255(little if any changes)
-Changed CHT temp Sensor(9L8Z-6G004-E)
-VOILA!!! Fixed, NO overtemping, no high running fan. Temp numbers verified on OBD2 again.
-BUT----Less than 100 miles later, P0128 code. (I think whats the big deal, but obviously car doesn't like it)
-I test the temp numbers of the Thermostat housing using an Infrared thermometer and they are the same as the CHT temps sensor numbers.(so I assume I have an actual under temp condition now).
-Car now takes a good 30-45 minutes to warm up to the 190 thermostat temp. Eventually gets there, but even in this cooler weather will cool down on drives as much as 160 degrees.
-SO, I pull the thermostat and test it in boiling water with a temperature gauge in the water and it works as advertised. Opens slowly around 185 degrees. So no Thermostat problem?
WHERE DO I GO NEXT? My only play at this point is to try another thermostat, but I want to pick other people's brains before I go changing something that I just replaced.