speedo problems

[41ook_patrol]

hey all i have a gq wagon and the speedo has started playing up sometimes it wont work at all, or it goes up to 120 and gets stuck there, or it goes rite over to past 180 and stays there.
sometimes if i tap the cover it works but next time i drive it it stops working.
any ideas would be helpfull

thanks

[97_gq_lwb]

Dry joints maybe

[41ook_patrol]

i thought maybe the wiring, plug or the needle

[sibbles]

I believe the speedo is electrical on all GQ´s so I would check the wiring. Most likely culprit on other cars I´ve worked on is down by the transfer case or up by the dash.