Funky Instrument Cluster

[R.O.R-2.0]

ok, so the cluster on my 92 jetta acts funky.. if battery voltage is high (fully charged, low draw, stereo off) then the gauge cluster reads high.. the fuel gauge and temp gauge will both read high..

if the stereo is goin, and its wet out, allowing the alt belt to slip, then the gauges read low..

i was thinking it was the voltage regulator on the fritz..

[ORCoaster]

Probably the regulator but you might try a check on the ground as well, that has caused me low readings on the gauges and my charging system was fine.  Have a volt and amp gauge on separate wires so I knew the incoming information was good.