I have a 96 ranger 4.0l auto the temperature gauge only reads 1/4 after the trucks been warmed up so I replaced the thermostat and ran It again, and got the same result. Anyone have any ideas is there any tests I can do to see if it's an issue with the gauge or temperature sensor.
Thanks for the help

Coolant Temperature Sensor:

With a good digital ohmmeter...

73 ohms when cold, 9.3 ohms at 'hot' which Chiltons says is 190-210 degrees fahrenheit.

Okay thanks, ill give that a try tomorrow.

If you haven't... make sure the cooling system has no air in it.

Also, the sensor needs the proper voltage from the computer to the sending unit. I don't know and I can't find it in Chilton's online manual. Once in a while, the computer's ground goes funky.

Before you put the temp sensor back in, clean the sensor end if it has slime or anything on it.

1/4 of the way up sounds about normal on the old fords...my 95 escort read the same and the heat was so hot it would cook you

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For the Rangers, it should always be in the middle. 1/4 way up, something is wrong.

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Where will I find the sensor i dont have the chiltons book yet,

Looking at the casting that houses the thermostat (where the large radiator hose connects, upper engine, front and center), there are two sensors.

The one on the right, with two wires is the one that communicates with the computer. If your vehicle had electric fans instead of the belt-driven type, this would be one thing to check for incorrect cooling temperatures.

The one on the left is the temperature sending unit which works with the gauge. It has one wire. You measure the resistance between the top terminal and the metal base.

By the way... I once bought a Motorcraft poppet style thermostat from a Ford dealer for my daughter's Mystique because the old one was sticking. After I installed it, the temp gauge would just touch the lowest of the normal range... no more. I took it back out (after checking the sensors) and lo and behold, the brand new thermostat's poppet was crooked, causing it to bind and stick open.

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By the way again ... if you have a library card ... your community's library (or any other library that honors your card) might have Chilton's available to you for free, online. Ask the bespectacled library lady next time you go there.