My tacho needle on a 88 carbie magna jumps sometimes
It also has power issues and fuel consumption issues. Just wondering if this could be related to a faulty distributor or something?

Mine does same, especially when the aircon fan is on.

gen1 tachos are crap, mine jumped too, it would also wobble/fluctuate when i would slam it back a gear whist flooring it, i looked in to it further and noticed that all gen1 tachos are loose and crap so i solved this issue with the digital dash :P
another idea i had was get the actual unit from another car and find one that was smoother but i didnt do much about that just went ddash instead

While the tachos are rather crap on the First Gens, i also had a problem with mine that resulted in the old plastic joiner (plastic over metal spade connectors) melting and shorting out.

This was the main connection between the fuse box under the bonnet and the igntion circuit, i simply replaced it and everything was fine although a week or so later this happened again, it was because i had connected extra things to the ignition circuit and was simply drawing to many amps through the stock wiring and the connection was the weak spot.

I just ran a new cable and a small fuse box of the battery and the problem was solved, then i went and got my KR :)

Hope this helps.

---
PHR33K

The digital dash comes in the upper spec magnas doesn't it?

hmmm anyway just a run around car so don't wanna spend money on it. I was just thinking maybe this is something to do with the distributor