I was driving around yesterday, seeing if I could get the gas light to flash in a corner with 3/4 tank(could not do it) and my tach started to work sort of sporadically. It would not match up to the RPMs, would stick around 1500-2000, then later on it was working again, would this be a loose connection or something? Or maybe a mechanical problem, the little needle hanging up somehow. It did not move when I jiggled the gauge, if that is helpful

check the connection at the coil - sometimes these wires are only hanging by a thread. sometimes the wires break internally from all the vibration.

you may be able to isolate this by swapping in a spare (friend's...) tach to see if it stays with the car or follows the tach.

hey check your points too.....

my tach acted just like yours, and it didn't hit me until my car stopped sparking on a major KY interstate....(I-71) at rush-hour....



b

If you wanna drive to Napa, I have a mess of tachs you're welcome to try out.

A drive to Napa sounds nice actually, I have someone with a few here I could try, but I am putting the ignitor on next weekend, so will be right there, moving the points from the distributor to the trunk. I figured it was something like a loose wire, makes a lot more sense it is in the engine compartment than the dash too.