Im trying to hook up my amp. & temp. gauge in my 68 console it came to me with out any wire harness I have them hooked up with wires the right way but they don't read right the temp gauge stays on 0- intill you turn the key on then it pins it's self below 0- and after you run the car hot it still won't move off below 0-,its a new sending unit also if I take the sending unit wire off and ground it , it burys the needle +. as for my amp. gauge the needle sits in the middle with the key off , if you turn the headlights on it - 1/4" when you turn the key on it pins its self + and won't move thanks for any help, Steve

The temp gauge sounds like it is working correctly, in that if you ground it it pegs the meter high. The temperature sender is nothing but a variable resistor that reduces its resistance as the temperature increases. There is supposed to be a resistor on the back of the temperature gauge. Is it there? You also need to add a ground wire to the rear (closest to the dash) gauge group, as the console cluster harness only has a single ground that attaches to the front gauge group. Without the ground, and the resistor the gauge will drift to one end of the scale and just stay there.

Where did you connect the two wires off of the ammeter, because something is definately wrong with that installation. Turning the key on should have no effect on the position of the ammeter needle (as long as your not starting the car) and it definately shouldn't peg high. The two wires from the ammeter both go into the engine compartment, one wire attaches to the terminal block right in front of the battery, the other wire goes the the horn relay terminal. The ammeter is really just a millivolt meter, and it monitors the voltage drop in the #10 Red wire that runs from the battery to the horn relay. If volts are higher at the battery that means the battery is being discharged and the gauge reads on the minus side of the scale. If volts are higher at the horn relay end of the wire that means current is flowing towards the battery charging it and the gauge reads on the plus side of the scale.

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Mark Canning
1969 Indy Pace Car
350/300HP RPO Z11

Do you have the correct sender,one for a gauge?I've tried one from GM and NAPA,both read to high.I finally bought a Standard Ignition, sender,PERFECT.I have my amp gauge connected to the alternator,and battery block.I installed a inline fuse in the wire at the battery.I know the installation is not correct,but it works.

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68 z28 ,68 rs 327 ,73 454 vette, 2 goofy kids