I have a 99 SS Camaro and my coolant temp needle doesn't move at all after the car has warmed up. I hooked up my bluedriver OBD2 sensor and the live data shows the temperature around 180 degrees. I turned the car on and used the volt meter on the plug for the driver side cylinder head sensor and it read around 2 volts on a cold car. No codes or check engine lights. I am confused because I read that there are more than one temp sensor (head and near water pump) and that the one on the head goes to the gauge and the one near the water pump goes to the PCM. Any help?

 

Welcome to the site! Only the '98's show true readings. From '99 onwards, (in response to customer worries/complaints) GM added circuitry to the gauge cluster that turns it into a 210 degree zombie if the true temperature is close.

There are threads somewhere on this site on how to alter the circuitry of the gauges to get closer to "true" readings like the '98's but I don't recall very many people going to the trouble to make the change.

 

Thanks! Actually I slapped the dash and the gauge went from full left to the zombie 210. Easy fix!

 

Ah - I didn't realize it was frozen at the low end.

Are your gauges or the gauge faces stock? If not, then there could be some other causes.