My buddy who has the exact same 98 GTS as I do (our VINs are literally two digits apart) recently took his car into the dealer because the temp gauge in the dash is not working. When we connect an Ultragauge to the OBDII port, it reads the temperature perfectly. The Dodge mechanic insists the temperature sensor is broken. My friend sent the e-mail below to the mechanic, and while he waits for a reply, I thought I'd post it here in case you all have a better idea. Text to E-mail to Mechanic Before you change the temperature sensor, please ask the mechanic to answer one question, because his diagnosis of a bad sensor does not add up to me. If you measure the temperature off the OBDII port, as my Ultragauge does, it reads the temperature properly. How is it possible to have a bad temperature sensor and yet still have the temperature read out properly? Isn't it more likely there is a problem between the mechanical temperature gauge in my dash and the ECU or wherever it draws its signal? If this isn't true, how is it the OBDII port perfectly reads the temperature? I know when I looked at it, when I disconnected the temperature sensor, the OBDII port could not read the temperature. When I reconnected it, the OBDII port read the temperature correctly. How is that possible if the sensor is bad?