I have a 99 grand am, ive changed tge thermostat,sensor,water pump and resevoi, at first the gauge would go to normal temperarurenad would drop to zero and be going back and forth, but after replacing all those things now it just stays on zero.
Could be a short in the wire from the sensor being that it stopped working completley after replaced
I ran a wire straight from the sensor to the plug thats located by the alternator and it was the same thing.
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