okay radiator was bad in my totaled camaro... rebuilt everything and put in a used one.. well tonight i started up for first time and not quite sure if antifreeze is going through engine... she runs good... and the radiator is getting pressure.

how long till the engine temp gauge should start rising at idle?

and any reason why low coolant light staying on....?

 

If it's just idling it might take 5-10mins. before the gauge moves, and the low coolant light, you prolly need more coolant once the thermostat opens, after that and it's still on, the sensor is more than likely bad.