[Vwdiesel] Stock Tachometer

[Rudy]

The Tach in my 85 Jetta works intermittently.  Sometimes when I start it it
works and sometimes not.  Sometimes it will start working while driving and
when I look at it again it's not working.  I've tried turning on and off
accessories and it doesn't seem to have any pattern that I can't see.
 
Anyone had this problem with the stock VW Tach or have any ideas where to
start looking for the problem?
 
Rudy