Hi all,

My rpm meter lives his own live, at least sometimes.

Under normal conditions it will do, but when you go up in the revs or at the highway, it runs to the end and will not come back until you stop for a while.

How does it work? Does this sound familiar to anybody?

Well, I believe it runs directly off the + side of the coil. It may have a loose connection or a bad ground. Or the tach is just plain worn out, have you tried a different one by chance?

One other thing you might check is the contact at the ignition fuse in the box. Doubt it would be the trouble, but with an electrical problem it never hurts to check the least obvious places too.

Never taken one apart so I'm no help there.

2many may have hit it on the head - check BOTH pos. & neg. conections at the coil. I had a loose ground there that caused the same problem. Try one thing at a time.. check by driving it after each check so you will know what it was that fixed it. good luck--

P.S. should the tach. ever be below 6000 r.p.m. ?? HAHA:D

Just thought of one other place to check. If you have done any repairs to dash lights or anything like that, you might want to double check the wiring harness plug on the back of the tach. It might be loose or possibly has some corrosion. If I remember correctly the plug is one of the hard plastic plugs without the positive type locks that some of them have. I'd explore all the wiring possibilities before yanking the tach out to replace it. Might also be a good thing to double check your connections at the ballast resistor if you still have it. I believe they are all on a common ground. Just another random thought.

Hi there jeff, should it ever be below 6000rpm probably not but mine can't even reach that it gets to about 4500rpm and moves about 100rpm for every 500rpm the engine is actually doing. Don't know why haven't figured it out yet.

Just thought of one other place to check. If you have done any repairs to dash lights or anything like that, you might want to double check the wiring harness plug on the back of the tach. It might be loose or possibly has some corrosion. If I remember correctly the plug is one of the hard plastic plugs without the positive type locks that some of them have. I'd explore all the wiring possibilities before yanking the tach out to replace it. Might also be a good thing to double check your connections at the ballast resistor if you still have it. I believe they are all on a common ground. Just another random thought.

2ManyZs

You hit the nail on the top. I replaced my dash because it had cracks in it. In other words I changed over the whole wiring because the other dash was a European one.

I will use my ‘snake’ trick again and crawl under the dash. If I find anything I’ll let you all know.