Mine always reads low in the winter, and normal in the summer. And I've changed it twice. Remember this engine has 2 sensors. One sends its signal to the gauge, and the other sends its signal to the computer. So I low reading on the gauge doesn't mean the temp is actually low. But changing the T-stat is always a good thing when you don't know the engines history.

Ok just ran out and verified the location of my gauge temp sensor (didn't want to pass on bad info). It is in the pipe leading to heater assembly BEFORE the thermostat. All part of the thermostat housing. Which means it sees colder water than the sensor for the ECM which is after the t-stat. This also accounts for flucuations in gauge reading with the heater on/off etc.

Hope this helps

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