I have a 1971 240Z that has a tach that operates intermittently. There are days it works fine, other days it stays at a fixed reading. I want to get it working consistently. Suggestions, ideas? Thanks.

Ken, Welcome! I do not have the answer to your question however, on this site (and other Z sites as well) you can use the search function to surf through the archives. Pretty much every question for repair and or modification has been asked and done before, so as you can imagine, there are a load of answers. Hope this will help you in your sesarch for an answer....and again, welcome aboard!

Thanks. I'll check that out. I bought the car about a month ago and am addressing the items that need attention as I find them. Overall, I am having a ball with the car.

I asked this question years ago, so far no-one has been able to give a satisfactory answer.

My thoughts are that it may be ground [earth] related.

Good luck and post the solution if you find it.

MOM

isn't the tach powered through the dizzy? i'm having problems w/ mine, and i think the PO may not have hooked up the electric dizzy properly....

The tach actually picks up from the points. Break that connection and engine no go.

Basically, there is a transformer type connection which converts the pulses from the dizzy to an analogue re-out [tacho]. If the connection is broken or intermittant on the other side [tach] side then the engine will run with no tach readout.

This is why I think I have a problem in the tach return wiring, but I really don't want to pull the dash to find the loose connection.

tomorrows my "work on car" day, so i'm gonna troubleshoot. i'll let ya know if i find anything miraculous!