jumping autometer tach

[Hiitman]

so i installed an autometer phantom tach. tapped the correct wire (#58 white). problem is that the tach is inconsistant. it doesnt increase smoothly. it sputters in a 2-300rpm range. any suggestions ?

 

[15psi88]

Maybe a loose ground? Other than that, might just be a faulty tach.

 

[kmoore]

so i installed an autometer phantom tach. tapped the correct wire (#58 white). problem is that the tach is inconsistant. it doesnt increase smoothly. it sputters in a 2-300rpm range. any suggestions ?

something wrong with the one in the cluster?

 

[Hiitman]

ill rewire the ground. its connected to the same ground thats used for all the backlights. maybe it needs its own. and for the stock cluster,no i just wanted to build something different. saw it in a mag on a nissan silvia. my cluster from left to right (all autometer gauges) is oil pressure, boost, tach, wideband, and fuel pressure. then in the center vent ive got water temp, egt, and fuel level.