Hello,

The temperature you are seeing is the equivalent of an open circuit on the K type thermocouple, so there is also a chance the black data cable going between the ECU and the front of the turbine is bad. Check that first. If a different cable does not fix it, it sounds like you need a new temp probe.

I believe Bob is letting handy guys change it out themselves but you should call to verify, not everyone is comfortable with that type of repair.

Hope that helps,