Hello evom. I recently got the p0125 code. It's temperature sensor failure from what I read around online. However, my temp gauge in dash works without issues although I have not tested the sensor element itself with a multimeter to measure resistance.
Could somebody shine a light on what may cause this cel?
By the way, car has had rear o2 delete for over 5years now with tephra

Edit: i pulled another code in addition to P0125.
P0170 Fuel Trim Malfunction (Bank 1)

Does this ring a bell to anyone?

 

The dash gauge has its own sensor on the front of the T-stat housing. Temp sensor for engine is entirely different, it is on the back side of the T-stat housing

Check for corrosion on the connector terminals to the sensor. other than that, replace it

 

Have you changed anything recently? Anything at all about the car? Thermostat, tune, anything? Is the rear O2 enable in your ecu periphery bit set to 1? If not, it needs to be, even with tephra.

 

i will probably check to see if resistance in temp sensor changed before replacing this.

nothing has been changed. this came out of nowhere.
im thinking at the moment

1. front o2 sensor failure
2. thermostat sensor failure

I want to get some inputs before i start swapping parts.

 

^This. Your coolant temp sensor is crucial to your fuel trims so could also be the culprit for your other code. Check the resistance relative to the stated value in the manual if it its off then you know your answer. You can also just log coolant temps and see if they seem to be way off...

 

it turned out to be just a bad front 02 sensor.