Rpm gauge reads all over the place. Today it read 1000 while idling and I know it was not at 1000. I tapped the glass on the gauge and needle started jumping around until it started reading close to being right. Fuel gauge same thing and it hasn't worked for a while, I thought it was maybe the sending unit, but when I tap it it moves around. Is this a sign of bad gauges?. They are Honda gauges on a 2001 sea chaser center console with 115 Yamaha. (If that matters)...any input is greatly appreciated