I have an 84 camaro Berlinetta and recently noticed that the electronic speedometer is bouncing around when driving. The numbers on the gauge will jump up and down even as I am driving at a steady rate. I was thinking the speedometer cable is about to go but have been reading that this camaro didnt have a cable. Any one have experience with this before for this model? Also I was thinking of just taking it to a chevy dealership to have it serviced but not sure if there would be any difference in taking it there as oppose to my neighborhood mechanic shop. Thanks!