Tachometer Issues
08-14-2022, 04:25 PM
#1
1st Gear
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Tachometer Issues
Hi long time reader, first time poster. My 78 seems to have issues with the tachometer reading either 0 (at idle) or 3500 (when giving her gas), sometimes it reads fine then all of a sudden the issue begins again. Not sure if its a problem with the filter or tach board. Searched the forums and didn't find much help. Any advice would be appreciated.
08-14-2022, 09:36 PM
#2
Le Mans Master
Plenty of threads on tachs..
bypass filter see if same issue or not…
replace tach board
bypass filter see if same issue or not…
replace tach board
08-14-2022, 10:11 PM
#3
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Sounds like classic symptoms of a bad board.
08-15-2022, 02:55 PM
#5
I had similar tach problems last year. Replaced the tach circuit board. Didn't fix it. Replaced the tach filter and it cleared things up...for a little while. After de-winterizing this year, the tach has started acting a little "wonky" again. By "wonky" I mean it works about half the time. Sometimes I start it up and it pegs...sometimes it works just fine. "tis a head-scratcher...
08-15-2022, 05:18 PM
#6
Le Mans Master
I had similar tach problems last year. Replaced the tach circuit board. Didn't fix it. Replaced the tach filter and it cleared things up...for a little while. After de-winterizing this year, the tach has started acting a little "wonky" again. By "wonky" I mean it works about half the time. Sometimes I start it up and it pegs...sometimes it works just fine. "tis a head-scratcher...
08-15-2022, 07:13 PM
#7
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Back around 2005, give or take. My tach was acting just like the OP's . very same symptoms. New tach board from one of the vendors. Pain pulling the drivers side dash out. But tach has been fine ever since. I did try a new tach filter first. No difference.
08-15-2022, 08:32 PM
#9
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Maybe you just got a bad one??
08-15-2022, 09:05 PM
#10
Le Mans Master