Brazilian Dodge Dart 76 (similar to 69 usa)

I'm having some problems with my temperature gauge.
I've tested it with resistance probes.
Using a 8 ohms resistance, it shows correctly the high temperature
Same to 23 ohms resistance (mid temperature).
Although, gauge does not move when using a 70 ohms (neither a 55 ohms) resistance.
In sum, it is not showing correctly low temperatures.

dam't .. these small things turn me crazy