Electronic Tach Question
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Joined: Nov 2004
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From: Flower Mound Texas
Electronic Tach Question
A circuit board replacement is supposed to fix 95% of all electronic tach problems, right? I guess I just happen to fall in the 5% category.
Where is the tach filter on these cars (I have a 75)? Is it engine side or dash side? It doesn't show up on my wiring diagram, but maybe my 40 year old eyes missed it the 50 times or so I went looking for it.
Where is the tach filter on these cars (I have a 75)? Is it engine side or dash side? It doesn't show up on my wiring diagram, but maybe my 40 year old eyes missed it the 50 times or so I went looking for it.
Race Director
Joined: Sep 2002
Posts: 10,362
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From: San Diego - Deep Within The State of CONFUSION!
Originally Posted by Razorhorn
A circuit board replacement is supposed to fix 95% of all electronic tach problems, right? I guess I just happen to fall in the 5% category.
Where is the tach filter on these cars (I have a 75)? Is it engine side or dash side? It doesn't show up on my wiring diagram, but maybe my 40 year old eyes missed it the 50 times or so I went looking for it.
Where is the tach filter on these cars (I have a 75)? Is it engine side or dash side? It doesn't show up on my wiring diagram, but maybe my 40 year old eyes missed it the 50 times or so I went looking for it.
Drifting
Joined: Oct 2003
Posts: 1,330
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From: Kerrville Texas
I've had to replace mine and I found that Rodney Dickman has them for less than the catalogs I think he might even be the one who supplies them to everyone else. Search for him on the web and he will come right up. He offers both the correct looking one for around $50.00 and one for $25.
By the way the filter is silver and about 1 1/2 inches long you cant miss it.
Kona
By the way the filter is silver and about 1 1/2 inches long you cant miss it.
Kona
Drifting
Joined: Aug 2004
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From: Fayetteville NC
Originally Posted by SanDiegoPaul
I had similar experience - replaced the board AND the filter and yet my tach still reads wayy too high.
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From: Flower Mound Texas
Originally Posted by KALAWAY
Is there any way to tell which one you need, board or filter, without buying them first? Is the circuit board located in the dash near the tach itself?
There's got to be a way to troubleshoot a tach problem, but I don't know what it is. It would have saved me $60 on the tach circuit board.
BTW - Turns out my 40 year old eyes are not deceiving me. There is no tach filter on my car. Now the $64,000 question - is that why my tach isn't working. I would expect a tach filter to clean up the signal from the distributor leading me to further expect that a faulty or missing tach filter would only cause the tach to jump around on occasion caused by the noise. But that's not what's happening with mine. I start the car and the tach goes to 1000 RPM and doesn't move after that - not after revving or after shutting down. Just sticks at 1000 RPM. I'll let you know once I figure it out.
