Pulsating Voltage in Gauge Wires??

Yep, normal if you have the original IVR (Instrument Voltage Regulator). That is how they work. I have had at least two bad temp senders over tha last few years. The chineseium parts are crap. I am not entirely sure that I didn’t damage one by over tightening the nut on the wire. Check the sender with an ohmmeter before you install. Should read 70-80 ohms at room temp.