So my temperture gauge in my 99 civic lx just shoots up to hot things ive tryed is filling the radiator resovior changing the fan switch the thermostat and the temperture sender still no go my fluids are good and i dunno what else i also checked the fuses what else can this be a faulty gauge cluster or what

 

Does it go to full hot as soon as you turn the key to the "ON" position without starting the engine???

 

Yes it does right away.

 

The single wire temp sensor that threads in to the head below the distributor may be faulty, OR the wire that connects it to the gauge cluster may have a short to ground. Either of those could cause that indication. Try pluging another sensor in to your harness and touch it to the engine (this sensor must be touched to the engine to work because the engine is it's ground), have a friend sit in the car and turn the key on and watch the temp gauge. If the gauge still pegs you have a short some where between the sesnor and the cluster or the cluster itself is bad. To eliminate the wiring, hard wire the sensor to the back of the cluster.