Here is a video of the burner running when started from cold:
https://drive.google.com/open?id...lJUHzIzDd1Sx6bW7xbLVy8uU

It starts and runs for 20 seconds or so, then cuts off.
After about 90 seconds there is a loud click and the ignitor lights up again, but no gas so no flame.
It continues this cycle where the ignitor glows but no gas until I turn it off.

If I turn everything off and try again it will not burn, but if I wait 10-20 minutes it will start the burning once.

I used a multimeter to check all the parts on the burner assembly (2 temp sensors, flame sensor, gas valve solenoids) and they all measure in range when disconnected.

I am assuming it is temperature related, but bypassing the temperature sensors results in the same behavior. Is the flame sensor sensitive to heat? Is something else overheating?

Thanks for any advice.