Tachometer Needle Jumping

As far as I've noticed my tach needle started to jump through the RPM ranges last night. It does not matter if I'm driving normal or spirited, the needle just seems to jump around but only as I accelerate. When I'm doing a constant speed the needle stays put and seems to be reading properly. Any clues or suggestions?

Could be a loose wire/connection at the cluster or dizzy. Could also be inside the dizzy.

WORPsol wrote:Could be a loose wire/connection at the cluster or dizzy. Could also be inside the dizzy.

I've been reading around and the general consinus is the ICM. I've got a friend who is going to let me borrow his dizzy for testing. I've also noticed that past 3k rpm the car kind of... Misses? If that's the best way to describe it... I've never replaced the rotary and cap, so I'm starting to think maybe it's time to change those out. But I'll test the dizzy first since it's so easy to test.

Yeah with it breakin up at high rpm's sounds like a rebuild is in order.

Well, last night I tood my cap off and cleaned up all the connections and made sure everything was night and tight. So far today everything has been working perfect, we will see. I'm a big fan of if it's not broken don't fix it...

I have known moisture getting in side dizzy's and causing alot of probs. They can even foul out plugs. Check your plugs too.