Tach runs backwards...
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Joined: Jun 2004
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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by ACECO
It doesn't work that way. The analog tach movement is driven by an electronic board that converts the ignition pulses into a variable signal that moves the needle. If the pulse input from the distributor and ground were reversed, nothing would happen. In other words the tach wouldn't move at all.
If the tach is moving backwards then either the circuit board or the tach movement has an issue. The movement itself is capable is turning nearly 360 degrees, but normally the signal driving it wouldn't do so. The fact that it is points toward an issue with the board itself.
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If the tach is moving backwards then either the circuit board or the tach movement has an issue. The movement itself is capable is turning nearly 360 degrees, but normally the signal driving it wouldn't do so. The fact that it is points toward an issue with the board itself.
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