Sounds like a loose connection at the coolant temperature sender. Or, the truck is low on coolant and air bubbles are passing by the sensor. This, along with a gurgling heater core, is a classic symptom of coolant that is too low before the truck overheats. Paying attention to these clues allowed me to fill up a friend's truck with coolant as it was almost a gallon low, and he didn't even know it was leaking (Dexcool). If you are losing coolant, you may have an intake leak. It is a common problem around 65 to 80 thousand miles. I would have this checked, you most likely won't see a leak, unless you look from below by the back of the intake. It ususally drips out there.
An automobile temperature gauge can fluctuate when the thermostat is opening and closing erratically. The temperature gauge can also fluctuate when the ground wire is loose.
The temperature gauge on a car fluctuates because the car's thermostat is opening and closing. The gauge goes up when the thermostat closes and the gauge goes down when the thermostat opens.
We replaced the temperature gauge in my 1991 Chevy blazer what is the normal operating temp?
A short in the turn signal wiring can cause the voltage gauge to fluctuate. A loose ground wire can also cause the gauge to fluctuate.
The sending unit in the fuel tank is probably bad.
on the side of the radiator
what would cause a oil pressure gauge to fluctuate on my 99 Chevy truck silverado i change the sending unit it does it mostly after it warmed up
Possibly the thermostat is opening and closing with the water pressure changes. Could be low on coolant also.
My Altima had that problem and it was the water pump going out. It started with temperature gauge was moving, but then it started leaking and finally the heater stopped being warm at idle.
1990 Chevrolet Lumina temperature sender is located on the back side of the thermostat housing. The sender has a wire that goes to the temperature gauge.
Check coolant level Could be thermostat opening and closing due to engine coolant temperature flutuation
Potenially a bad temperature sensor or bad contact on the wire connector. Test for set voltage resistance according to temperature.
Bad temperature sending unit? Bad gauge?
you can buy the gauge at any auto store or even walmart and there are directions with the gauge.
210 to 220 is a safe range.
bad temp sender usually. Bad gauge rarely.
Buy a new Speedometer cluster. The external Temp gauge is extremely rare
get a new temperature sensor.
seriously? it tells you what temperature you engine coolant/antifreeze is. that is how your gauge on the dash knows what your temperature is at.
Mine does not. Perhaps you a low on coolant.
195 degrees F