Speedo and Tach

I have a 95 VR6. Occasionally on the first start up of the day the Tach and Speedo dont work . All other gauges work . They malfunction for a couple minutes to 20 minutes. When the key is first turned on and after engine is running , the Tach needle just pulses . Any ideas on this one??? thanks

No Idea, however my tach does the same thing, I have a 92 jetta diesel...
I think my problem is perhaps a corroded wire, cause at times it will be working fine and then I go over a bump and it stops and then starts working at the next bump in the road.

I suspect mightestmike is right considering the tach and speedometer have different input sources.

You have a bad instrument cluster.

New one from dealer is 350-450.00 at least.
You can, however, remove the cluster and take off the back pannel and spray some zep elec electrical parts cleaner on the circuit board and it normally fixes the issue for 6months or so.