My brand new spartan3 that I just installed always keeps blinking at about 2 blinks a second.
This is with a brand new sensor you provided.
It does it immediately after cranking when engine is cold and after it has been running for a few minutes.
The car is a 90hp Miata and I don’t believe that it would instantly overheat the sensor.
The AFR readings are also stuck at 13.3.
Connection wise everything looks good, the controller to megasquirt works fine. I have verified that the controller gets power and
I’m experiencing a very similar behavior with a new setup… the red light immediately flashes quickly. My sensor’s heater circuit seems to measure properly with a multimeter.
During the initial heatup it is normal for the sensor to show too hot for a few seconds and then quickly settle to the correct temperature. After the initial heatup the LED should not blink.