What did you do to your kombi today ?

[Doob]

With regard to the erratic Tachometer ... I had the same problem .. I checked all connections, replaced the ignition condenser .etc..but I still had the problem. I am guessing there is some electrical noise source that I could not find & eliminate   In discussion with instrumentation guys it seems the standard fix for older vehicles is to add a diode to the lead from the -ve ignition coil terminal to the distributor. I inserter a 4004 diode and the tacho has worked fine ever since.
See attached a Service Bulletin from AISAT Instruments in relation to VDO ignition Tachometers.