2 different cars, 2 different autometer gauges same thing. nothing is loose all connections are good its been double checked and been completely redone twice.
i even isolated the gauges onto their own circuit with the own grounds. routed the signal wire away from any possible interference, and with all loads on(heater, lights, 4-way, wipers, etc..) it still does it.
you are not alone, but my theory is when there is high load on your battery alternator, the other accessories demand more power and since it doesnt take much amps to run a gauge the gauge is the last priority, the larger drawing accessories steal the power from the little one basically.
another thing i noticed is that the light bulbs they give you suck get rid of them! they make the gauge super hot which effects resistance. mine got so hot it could burn my finger if i touched it, just try and imagine that gauge working right if its over 100 degrees f. switch to colored LED bulbs, instead of those stupid colored condoms over intensely hot regular bulbs. that is what actually made the difference in my situation.
