Tach buzzing/scraping noise

[luigisho]

I remember reading about this years ago but can't seem to find it. Is this a cable problem or a gauge problem?

 

[sdpatt]

That would be the cable. The simple checks are for a tight bend in the cable between the speedo in the dash and the transmission post. Make sure the cable has the smoothest path possible. It way be worn beyond the point where re-lubing it can help, but graphited speedo oil can stop many noises.