My temp sender has not been working. It is brand new. A thought crossed my mind, when installing, I wrapped ALOT of teflon tape around the threads to avoid any leaks. Would this tape prevent the sender from grounding and not working?? This is on a '67 396 with a new temp sending unit, new wire harnes and rebuilt console gauges. The gauge moves to C when I unplug the sender and moves to H when I ground it. If the tape is causing the problem, do you have any recommendations for a sealer I can use that will allow the sender to ground?