Temp Gauge Acting Up

[Solid]

Temp Gauge Acting Up *Update*

95 ranger 2.3L 5spd man

OK, whenever i start up my truck, the temp gauge goes all the way to the top, then when i start going (maybe driving 2 mins) it'll drop back down to the bottom, then go back up to the top, and it'll repeat this a couple of times untill about 7-10 mins of driving then it'll drop to the normal position (1/4 of the way up)

Does anyone know how i can fix this or what could be causing this?

Thanks

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OK now i have a new problem. The temp gauge starts off pretty high

NOTE - this is with the engine OFF (for at least 4 hrs)

When i turn the truck on the needle will climb to the red line i drew on the pic.

Could it just be a bad temp gauge?

Thanks for your help

 

[Wicked_Sludge]

test the sending unit (the single wire sender is for the gauge), and check its ground (its grounded through its threads).

 

[chazzone]

You have checked your anti-freeze, and it's topped up, right?

-zz

 

[Bob Ayers]

test the sending unit (the single wire sender is for the gauge), and check its ground (its grounded through its threads).

Since the resistance of the sending unit drops as the temperature increases, any series resistance would make the gauge read lower, not go to the top.
Either the sending unit has an intermittent internal short to GND, or the wire going to the sending unit has an intermittent short to GND.