Strange 82 Tach Problem
Thread Starter
Intermediate
Joined: Sep 2012
Posts: 38
Likes: 0
From: Opelousas Louisiana
Strange 82 Tach Problem
I've searched through the posts and have tried most of the suggestions. OK to the point. So the tach will zero with the ignition on, will read about 500 rpm when the car is running at idle. But while in park, i can rev the engine way up but can never seem to get past 2500 - 3000 rpm nor will it go higher if driving and stomping the gas. So the ground and 12v are fine. From 12v to signal I get about .2v at idle and 1v at close to redline. I don't have the filter at all. I tried replacing the board with one from wilcox and the needle may work sometimes, may not work, go from way below zero to way beyond 7000, or just act the same as the original board. So do I need the filter, an actual new tach, a new tach and board or is there something else i might be missing?
Heel & Toe
Joined: Sep 2013
Posts: 21
Likes: 2
My tach was reading high, so I just put in a Wilcox board over the weekend, and also put a filter in, the tack is all over the place now. I set it at 0 with the key on, and it changes now every time I turn it on, it goes up and down at a stop light now with the blinker on. It worked fine before, just read a little high. Good luck!
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I've searched through the posts and have tried most of the suggestions. OK to the point. So the tach will zero with the ignition on, will read about 500 rpm when the car is running at idle. But while in park, i can rev the engine way up but can never seem to get past 2500 - 3000 rpm nor will it go higher if driving and stomping the gas. So the ground and 12v are fine. From 12v to signal I get about .2v at idle and 1v at close to redline. I don't have the filter at all. I tried replacing the board with one from wilcox and the needle may work sometimes, may not work, go from way below zero to way beyond 7000, or just act the same as the original board. So do I need the filter, an actual new tach, a new tach and board or is there something else i might be missing?
Melting Slicks
Joined: Jan 2014
Posts: 2,478
Likes: 254
From: Downers Grove Illinois
I changed my tach board due to the tach reading wrong. When I put it back together the readings were very erratic. In my case the problem was the nuts holding the tach board (ground) weren't fully tight. I had to take the dash completely apart tighten the nut and it has been great since then.
