I have a 96 with the 2.8 and recently the engine coolant temp was reading low ( barely getting off the lowest reading). Several searches talked about the coolant temp sensor on the coolant pipe, back of the engine, passenger side. I located it and just for the sake of elimination I pulled off the connector sprayed on some contact cleaner on it and the sensor and BINGO! thegauge was back to reading the correct temperature. Lucky I guess but something to check before you go thru replacing the sensor.

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