Ozmodiar-X

So i have an 83 12a engine in my 79 car, with the igntion changed from points to the electronic. The tach does not work, it just jumps around. When I'm driving with no electial load but engine it says above 8000 rpm. How do i fix this or is my tach just dead. I have an external one that works for me, it just would be nice to have the stock one work also.

7aull

iTrader: (2)

Is the tach reading in the "voltmeter" mode? ie reading voltage (something SAs are supposed to do when the ignition is "on" but car isn't running) instead of rpm. I state the obvious that its a wiring problem :p Might need an 83 AND 79 wiring diagram set to compare what wires are running where. These are downloadable in the Archive.
sorry - not much direction on this. Anyone else??
Stu Aull
80GS
Alaska

Rx-7Doctor

iTrader: (13)

https://www.rx7club.com/1st-gen-archive-71/ignition-points-electronic-ignition-conversion-msd-links-17474/

Ozmodiar-X

sorry, but what is that link supposed to show me? I read it and am not sure what you are tying to point out.

Rx-7Doctor

iTrader: (13)

Go to the thread in the link. Go to the link that someone has posted in there that has the detailed writeup on the wiring conversion. Verify that your wiring is correct.

Ozmodiar-X

oh, sorry about that. It is wired correctly.

Ozmodiar-X

bump