I've got a 91 Camaro 3.1 that was having an issue where the temp gauge would reach 240+ before the radiator fan kicked on, and it would switch off around 220. About a year ago i replaced the original coolant temp sensor and it fixed the problem- fan came on around 230 and switched off at 200. The car has done less than 3k miles since then and now the problem has returned, fan still switching on late and switching off too soon. Did I just buy a junk coolant temp sensor that needs replacing again? Rad and header tank are both full. Car has had a new radiator, thermostat, and water pump in the last 5 years. Previous owner removed all of the a/c components including the condenser so it runs cool unless i'm driving in traffic. Thanks in advance