flutering tach??? help please

[trav_19]

well in my 93 after i have driven it after awhile i notice the tach starts to get jumpy and it will start doing movements all on its own and sometimes it will bury itsself then bounce back then peg again and some times stay there....what could be the cause???? plug wires maybe..? there pretty new but i guess they could be bad

 

[19mustang95]

i have had the same problem...im interested in a fix for this too. i dont want to have to buy a ricer tach. :-\