T-STAT
2004 gmc envoy with code p0128
PO128 refers to the thermostat not operating properly. You could replace the thermostat with a good quality one such as Stant. The computer will have to be cleared. If the code does come back then you need to have a repair shop check it out for you. Code PO128 is engine temperature below specs. You can try changing the thermostat and have the code cleared. If that does not work then you need to pay a shop to further diagnosis it. jd
thermostat
P0128- coolant thermostat ( coolant temp below regulated temp)
Sounds like you need to replace the thermostat.
For 1996 and newer Trouble code P0128 means:Coolant Thermostat (coolant temperature below thermostat regulatin temperature)
I have the same van and had the same problem. The error code PO128 is an error code letting you know you need to specifically replace the Coolant Temperature Sensor. The Sensor is about $14.00- $15.00. Just a little work, not bad. I did it and actually helped my gas mileage also. I would recommend Advanced Auto Parts.
Either you have a bad temp sensor or your thermostat is staying wide open and letting the engine run to cool.
First check your coolant level,then change your "ect" engine coolant temp sensor.If that fails change your therostat and coolant.
BDTC P0128 Engine Coolant Temperature (ECT) Below Thermostat Regulating Temperature " I have seen this several times this week alone. All three times I replaced the coolant temp sensor and it fixed the customers problem. john f.
The check engine code P0128 on a 2004 Lincoln Navigator indicates that the engine is not reaching its optimal operating temperature within a specified time frame. This typically points to issues with the engine coolant temperature sensor, the thermostat, or the engine cooling system. A malfunctioning thermostat that is stuck open or a faulty sensor could prevent the engine from warming up properly, leading to decreased fuel efficiency and potential emissions problems. It's advisable to diagnose and address the underlying issue to ensure optimal vehicle performance.
The error code P0128 for a 2004 Buick Rainier typically indicates an issue with the engine coolant temperature being below the thermostat regulating temperature. This could be caused by a faulty thermostat, low coolant level, or a problem with the engine coolant temperature sensor. It is recommended to have the vehicle inspected by a mechanic to diagnose and address the underlying issue.