[niquehawk5]

Hey, I got a SES light last night on the way home so I pulled the code this morning and it came back P0128 for the thermostat. The odd part is I have heat, it was approx. 10 mile drive last night home with no overheating and everything seems to be acting normal today. Cold starts have no fluid running in the top radiator hose signaling that the thermostat is closed, but then it has fluid running after warm up as if everything is acting normally Has anyone else experienced a code like this? Is it possible it was just a faulty code and just keep an eye on it?

[N54sk8r]

I am currently dealing with this problem now , this will be my 3rd thermostat . But like you said when it warms up it goes away or if I turn the car off and back on and than I might not see it again for 24 hours or 3 days .

[niquehawk5]

I am also curious if maybe it is the coolant temp sensor itself. Changing that would be far less painful

[Lotus99]

Originally Posted by niquehawk5

I am also curious if maybe it is the coolant temp sensor itself. Changing that would be far less painful

So is it actually possible to change the sensor only? I've just replaced my water pump that had died, and as a preventative measure, replaced the thermostat too.

But now I'm getting two codes P0597 (Thermostat here control circuit/open) and P2EF7 (characteristic diagram thermostat, control), and My mechanic says I probably got a defective thermostat and need to replace it. But I'm wondering if this sensor is the culprit and might be easier / cheaper to fix than Replacing the thermostat?
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[wiskerbisskit]

The thermostat is electric and will malfunction in the open position so no overheating and you'll still have heat. Replace it with OEM and you'll be fine. Should take you a couple hours on stands, less obviously if you have access to a lift.

[niquehawk5]

Originally Posted by Lotus99

So is it actually possible to change the sensor only? I've just replaced my water pump that had died, and as a preventative measure, replaced the thermostat too.

But now I'm getting two codes P0597 (Thermostat here control circuit/open) and P2EF7 (characteristic diagram thermostat, control), and My mechanic says I probably got a defective thermostat and need to replace it. But I'm wondering if this sensor is the culprit and might be easier / cheaper to fix than Replacing the thermostat?
.

The sensor is on the front of the block, but honestly I don't know much about those codes. I replaced the thermostat and have not had an issue since.

[niquehawk5]

Originally Posted by wiskerbisskit

The thermostat is electric and will malfunction in the open position so no overheating and you'll still have heat. Replace it with OEM and you'll be fine. Should take you a couple hours on stands, less obviously if you have access to a lift.

Yep, exactly. I would never buy anything but OEM parts or fluids with this car. Seems to be the only way to go for proper fitment and function.