The in the dash tach on one of our cars is suddenly intermittant. It worked fine after the rebuilt dist install and re-timing. Now it has a very slight deflection which is much lower than the actual rpm. Without looking at the wiring diagram, I am sure the electronic pick off must be driven by the coil. This could be internal to the instrument itself. I saw something like this on a GSX hood tach once but thought I would ask Board members if they had suggestions for other possibilities. Jim Lore
I have a similar problem with mine. It dropped 500 rpm while I was watching it and it never has been accurate since. It still works but the accuracy is gone. I thought maybe a ground problem? Anyone?!!!!!!! Mike D.
