Engine is major, the other codes are optional.

 

OK quick update.

We are getting 4.99 volts to the IAT plug. When I check ohms on the IAT the meter does not change from open. When I checked continuity the number actually went above 1 and oddly did respond to the hair drier test.

 

OK we are making progress!

We ordered a bunch of parts off Rockauto because changing them early is cheaper than new antifreeze.

We drained the radiator and pulled off the thermostat housing...... No thermostat! That is the reason why we were only at 1/4 on the temp gauge most of the time. We also ordered a new temp sensor because.... it was cheaper than 2 gallons of antifreeze. Now for the question: How do I get it tight? I can barely feel it let alone get a tool in there. The old one came out with my fingers, I don't know why it was not leaking.

 

15mm crows foot.



Or you can modify a cheap 15mm socket:

 

Thanks! The old one came out with my fingers. It is amazing that it was not pouring coolant out from there

 

Previously replaced, without a proper socket wrench. To remove original, cut wires(just like replacing an o2 sensor) and remove with regular socket. However installing the new, you need a crows foot or modified socket to tighten. I modified a socket with a cut off wheel tool, and removed without cutting wires, and tightened the new 1 without a problem. I have thousands of socket wrenches and 1 is an H3 specialty socket.

 

We got the thermostat and temp sensor installed! Now the gauge stops right in the middle where before it only went to 25% then would eventually creep higher if we drove it long enough.

I cannot believe that there was no thermostat at all in there. It was a repo so who knows the real story.

Hopefully we will not have any more check engine codes. How many cycles does it take?

 

Erase the codes and drive, they should be gone immediately not to return unless the PCM detects the issue again.