hey my tachometer no longer works on my 87 gt. i found some melted insulation on the wires directly behind the intake. got that taken care of. fuses all check ok. still doesn't work. all other gauges are fine. when i turn the key on, the needle bottoms out and stays there. its been suggested that i replace the little circuit board that screws down to the back of the instrument cluster. i have one left over from when i replaced the cluster year or two back. just one thing, the little chip on the back of the boards are different in size. are the boards still interchangable? also, might there be any fusible links i'm overlooking? i was told the signal for the tach comes from the neg. side of the coil. is that correct? any ideas would be most welcome.
tachometer ain't workin
- Thread starter stang0f87
- Start date
Personally, I'd get a 5" Autometer and call it a day. 
In all honesty, if you have another tach to test in its place, that may or may not be a good idea. You said the melted insulation is taken care of, but what caused it, and is it directly related to the tach? If it was caused by resistance somewhere, I'd investigate further, to make sure there's no more melted wires that are making contact, causing your tach to go haywire. Hopefully Hissin or jrichker will see this and bring one of their lifesaving electrical schematics along, to point you in the right direction, since you'll probably be pulling hair out by the handful, trying to find the wires otherwise.
In all honesty, if you have another tach to test in its place, that may or may not be a good idea. You said the melted insulation is taken care of, but what caused it, and is it directly related to the tach? If it was caused by resistance somewhere, I'd investigate further, to make sure there's no more melted wires that are making contact, causing your tach to go haywire. Hopefully Hissin or jrichker will see this and bring one of their lifesaving electrical schematics along, to point you in the right direction, since you'll probably be pulling hair out by the handful, trying to find the wires otherwise.The Tach on my car broke, but its a 91 so it might be diff.
It turned out that there was three pins on the back of the tach assembly that touched three corresponding metal clips on the circuit board. Over time the clips spread apart, and i just needed to push them in for a better connection. Goodluck
It turned out that there was three pins on the back of the tach assembly that touched three corresponding metal clips on the circuit board. Over time the clips spread apart, and i just needed to push them in for a better connection. Goodluck
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