gas guage

[91sonoma]

Not sure if this is the right area for this. When my gas guage shows less than full it bounces up and down when speeding up and slowing down. Is this the float in the tank causing this?

 

[kennythewelder]

No, well yes, but, the gauges have a fluid in them ( when they are new) to prevent this. As they get old, the stepper motor( that driver the pointer needle) evaporates, or leaks out, or whatever, letting the needle bounce around. There are a few videos in you tube, about using some RC car diff oil to refill the stepper motor with oil, or you can order a new stepper motor from e-bay or amazon, but it has the be one for the speedo only. They do not interchange. I think there is a write up on here about fixing your stepper motor by refilling the oil. The RC rear diff oil to use it 30,000 visc I think.