My temp gauge keeps fluctuating. It will run with the needle between the Oand the R, and then climb between the M and the A, then it will climb back down, between the O and the R. Could it be a themostat problem, or a more serious problem, like a cracked head???? 1996 Ford F150, ex cab, 4x4, 302. Thanks in advance for any help.

 

If it's the in dash gauge, the sensor could be flaking out. It's located on the driverside top of the motor. It has only one wire going to it. If you ground it, the gauge should go full scale.

They cost about 6 bucks. I would put a regular temp gauge on it and see what it does

 

correct me if i am wrong but doesn't the coolant stay in the engine until it hits a certain temperature, then the thermostat releases it and allowes new coolant into the engine. does the coolant then get blocked back in the engine until it gets hot? if so, it could be continually doing this until your truck gets hot. i know in my truck, while it is warming up, if you watch the gauge it will get to the normal range then drop quite a bit because the new coolant is let in.

if it comes to something being bad, the thermostat is quite cheap and fairly simple to replace, if that is what is wrong.

chris

 

Mine does this on occasion too, sporatically. Have you checked the simple things like no air in the system, the radiator and overflow tank are at the correct level, radiator cap is seated properly?


(95 5.0, 2wd, stick, supercool)