Hi,
Have you checked the connector at the ECM? The two wires from the ECT run to the ECM, pins 4 and 58 of the X2 connector/black in color.
If you look at pics 1 and 2 below, I attached the schematic and highlighted the wires for you. Note they run to the PCM.
In pic 3, I highlighted the PCM/location for you to locate.
Since it works for 30 minutes, I suspect it is one of the pins at the PCM. They can corrode or even break. If you look at pic 4, I included the X2 connector pinout. I indicated pins 4 and 58. Check these. First, however, you may want to have a helper watch the gauge while you wiggle the connector to see if it allows it to work again.
Here is a link you may find helpful:
https://www.2carpros.com/articles/how-to-check-wiring
It sounds like a weak connector that is being affected by heat/expansion. Try this and let me know what you find
Take care,
Joe
See pics below.
Images (Click to enlarge)
May 24, 2022 at 9:12 PM
