Tach reading problem---tach filter or cluster??

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Apr 19, 2010 | 02:59 AM

65Z01

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From: SE NY

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Tach reading problem---tach filter or cluster??

Tonight was the first time at highway speeds since the motor rebuild and I noticed that at 64mph the tach readings were high and varying qite a bit, while at 55mph they were pretty steady and looked normal.

I ran the Auto X-Ray in Monitor mode to verify that the ECM was indeed seeing correct RPMs, i.e. 1600rpm at 64mph.

Any experience with this one??

Apr 19, 2010 | 08:09 PM

65Z01

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From: SE NY

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Anyone with input on this one, please...

Apr 19, 2010 | 08:19 PM

miscstudent

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From: Newbury Park Ca

Actually just did some research into this. What most people have found is that it is the tachometer filter is going bad. Replacements are $35 from Corvette Central

Apr 19, 2010 | 09:10 PM

WW7

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From: WV

If your scanner is saying the right rpm and the gauge isn't, it sounds like your tach filter...Go here and get the non GM filter for $22.00 , he makes them himself and they work great.. Plus shipping is just $4.00.. Ive had this same one on my 89 for over 3 years with no problem..WW

http://rodneydickman.com/catalog/pro...roducts_id=265