Rev Counter goes silent

[pafagt]

Hello forum, my rev counter stops working after a few minutes of starting the car. Is the rev counter on these VM cars electric could it be a wire or fuse problem or is it completely analog? Any ideas what could be the problem?

Thanks !
Pablo

[Heuer]

Tachometer is basically a voltmeter directly connected to the tach generator on the rear of the r/h cam shaft. It works by generating an AC voltage, 1 volt for every 100rpm. No fuses, no other power. Could be the generator as they are known to fail, drop voltage or the drive dog is moving out of the camshaft. Remove three Allen bolts and check.