Tach went nuts
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Joined: Mar 2002
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From: Madison al
St. Jude Contributor
Tach went nuts
After I replaced my plug wires my tach started jumping all over the place. The car is running fine so I have no idea what is causing it. While I had the steering wheel off, I pulled the speedo/tach panel and cleaned all of the contacts. It is still doing it. Any one got any ideas? :confused:
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Joined: Aug 2000
Posts: 3,909
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From: Clymer PA
Re: Tach went nuts (RLaFarge)
I'm not sure how different your '79 is from my '76 but it shouldn't be too much different. The same thing happened to me at one point.
There is a tach filter that is grounded to the intake manifold (at least on my car it was). If it is not secured to the intake, it will cause a bouncing tach. Also if one of the wires soldered to the tach filter is loose it will cause this. The tach filter may also be altogether bad. Any of the above could be a possability.
There is a tach filter that is grounded to the intake manifold (at least on my car it was). If it is not secured to the intake, it will cause a bouncing tach. Also if one of the wires soldered to the tach filter is loose it will cause this. The tach filter may also be altogether bad. Any of the above could be a possability.
