tach stops at 3000rpm ?? please help

[bustedfoxwagen]

i have a 92 eco diesel jetta and i bought a cluster from a guy in canada that had a tach on it, i out it in and it seems to be fine till 3000rpm it just bounces and comes down? any ideas whats happening? thanks
-Ben

can post video of whats happening if you think it'll help?

[QuickTD]

Posting your question in every forum here will probably annoy most of the membership and get you nowhere. The troubleshooting forum is only only place you need to post questions related to troubleshooting. Post the question once only and wait for an answer. We all read all the forums, no need for the multiple postings. Now on to your question.

 The tach is driven by the alternator, if the alternator is malfunctioning there is a good chance that it will affect tach operation. I would supect worn alternator brushes or loose connections on the back of the alternator.

[bustedfoxwagen]

look im real sorry i only ment to post in the idi and triuble shooting not "every" forum.. thanks for the help ill check it out tommmorow