tachometer filter!
Thread Starter
Safety Car
Joined: Jul 2008
Posts: 3,966
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From: Made In America
St. Jude Donor '10-'11
tachometer filter!
It just popped into my mind. What does the tach filter do on a car? I think I may have tracked down my issue. Does it filter out noise from the radio or anywhere throughout the car? What is it's purpose?
Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
The tach filter is an RC (resistance capacitance) low pass filter which greatly reduces the energy at high frequencies which prevents the tach circuit in the cluster from getting false triggers which would cause a tach reading that was too high in rpm and unstable.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
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From: Kempner Texas
As I understand it, the filter converts the electrical signal into something the tachometer can read.
I recall someone posted that his tach was able to work okay without the filter. Maybe he'll chime in on that.
I believe GM discontinued them, but I've seen them listed in one of the Corvette catalogs; either Corvette Central, Ecklers or Mid-America - forgot which.
Jake
West Poont ROCKS!
I recall someone posted that his tach was able to work okay without the filter. Maybe he'll chime in on that.
I believe GM discontinued them, but I've seen them listed in one of the Corvette catalogs; either Corvette Central, Ecklers or Mid-America - forgot which.
Jake
West Poont ROCKS!
Thread Starter
Safety Car
Joined: Jul 2008
Posts: 3,966
Likes: 4
From: Made In America
St. Jude Donor '10-'11
I just ordered mine from ecklers. I have been having trouble with my radio. I unplugged the tachometer filter and the radio works fine! I plug it back up and all hell breaks loose. Unplugged, the RPMs do NOT work on the digital cluster. Thanks though. One less thing to worry about.
