It jumps around like I have a bad connection. I checked them all and everything seems to be tight. Is there a chance the thermocouple is bad or is more than likely the gauge itself? Its an autometer phantom.

 

mine has the same problem sometimes it will just be all over the place. i dont know what the deal is.

 

I have the same problem, I changed the probe and it still did it so I changed everything except the power and gound wires. still have the problem

 

I would think you have a bad ground. I have had an issue similar with an Issopro gauge.

 

I've heard on here to take the connections apart on the probe wires, buff the eyelets up with sandpaper (regardless of how clean they look) and put them back together snugly. Might be worth a try. I've seen firsthand of how a small amount of nearly invisible fretting corrosion can cause problems in a delicate circuit.

 

Guages are less than a month old. All three guages are wired to the same ground, no problems with the other two. It could be a bad connection at the ground splice, not at the screw. Ill check that. It was doing it off and on for a while then it just went super screwy and is way off. Cruising down the highway where it used to sit at 700 it now sits at 400. len73, if you changed all that and it still isnt right, I would think its a bad gauge all together.

 

maybe a bit of dieelectric grease after you buff them up idont know its worht a try