Tach problem! Need help!
Thread Starter
4th Gear
Joined: Oct 2023
Posts: 4
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From: Locust, NC
Tach problem! Need help!
So here's the situation. I bought a '76 about six months ago and have slowly been going through it and undoing the decades of "wiring fixes". The tach has not worked since I bought the car and is stuck pointing at 1500. I have read through many posts from you guys on this issue and haven't had any luck getting it working. I replaced the board on the back of the gauge, installed the filter in line with the tach signal wire (verified function after install per manufacturers instructions), verified 12V at the plug, checked for a good ground, and checked the tach signal wire for continuity back to the distributor. I still have no movement at all on the gauge. Is it possible that the tach itself is the issue? I feel like I've tried everything else. Please help me out here!
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It really does sound like a tach board.
however, you replaced and nothing changed.
Did you check signal to the tach?
Just 3 wires to electric tach. Power, ground and signal. Signal of course comes from the distributor, power and ground are also easy to check.
however, you replaced and nothing changed.
Did you check signal to the tach?
Just 3 wires to electric tach. Power, ground and signal. Signal of course comes from the distributor, power and ground are also easy to check.
Thread Starter
4th Gear
Joined: Oct 2023
Posts: 4
Likes: 0
From: Locust, NC
I verified that there was continuity from the connection at the tach to the distributor. I am assuming that since the tach reads off of the negative side of the coil and the engine is firing correctly, the signal should be fine. The tach board I removed from the unit didn't appear to have any of the burns you normally see on these things, although I replaced it anyways. Still no luck....
