Ok guys, two weeks ago I pulled my plugs to check them. Upon completion I hooked up the battery then reset my stereo settings etc. The next morning I cranked her up and noticed my voltmeter down toward the bottom quarter of the gauge, so I traded cars to follow up in the afternoon. I have an SVE 3G set up with 4G power wire so I figured maybe I hit something messing with my plugs. Upon further investigation I find my negative battery cable had split (wire and connector separated). Replaced that. Did an entire system test with DMM which all under hood components tested good. Additional reading I see where the voltmeter and resistor are an integral part of the charging circuit. I pull the instrument cluster out and realize the copper wire back plate is damaged around the voltmeter / resistor connection. Test with DMM and no continuity. I solder the link and test again, now I have continuity. While in there I see I am missing the low coolant light and light socket. I replace that and put everything back together. Works like a charm. Next morning driving to work and getting on the on 75 on ramp ramp I noticed my temp cross the center line on the factory gauge. Never comes above center, since replacing the factory radiator because of a leak. I have an SVE 3 core. Coolant overflow works as designed and this drive usually nets about an inch to an inch and a half of additional coolant from expansion and returns to cold level when cool. In the days since I am noticing the needle drifting above center it continues to show elevation up to the bottom of the N in normal on the factory gauge. Low coolant light is on continuous too, not low though. I have burped with her jacked up and have a Mr Gasket 180 T-stat. I have been scouring this site looking for test options. I have since tested my factory gauge/wiring by un plugging the water temp gauge sending unit wire and grounding with key on she tests good, swings to top of gauge, remove wire from ground and it returns. I have replaced the sending unit, still the same, although it takes a bit longer (few miles) to swing passed the center position on the gauge. I am now at a loss. I would like to figure out what is giving me fits rather than replacing gauges as she is pretty much stock and does not need a host of autometer gauges. Someone help, ready to follow instructions!
Jason
Jason