Tachometer reading incorrect
Thread Starter
Burning Brakes
Joined: Sep 2005
Posts: 1,139
Likes: 109
From: B'ham Alabama
Tachometer reading incorrect
My 1975, (L82 / 4spd manual), tach seems to be reading incorrect. At idle, it "seems" to be reading correct. Reads right around 1000rpm,...and the engine sounds to be about that speed.
However, as you drive at higher speeds, the tach seems to be reading much too fast.
The engines does NOT seem to be turning up anywhere near that fast,..so I'm assuming the tach is calibrated wrong.
However, as you drive at higher speeds, the tach seems to be reading much too fast.
- At 60mph it reads between 4,000 and 4,500 rpms.
- At 70mph it's reading 5,000 rpms.
The engines does NOT seem to be turning up anywhere near that fast,..so I'm assuming the tach is calibrated wrong.
- Would this be a printed circuit board issue,...
- a distributor connection issue,...
- or a guage issue?
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,852
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
In this case the board would be the only thing I would try...
As the cars are aging I'm seeing more and more failures in the movements of the tachometers. While the board will probably solve your problem, there is a possibility the movement might be the issue.
I have left dash pad removal instructions on the web site should you decide to remove it.
Corvette Left Hand Dash Pad Removal Made Easy 1968-1977
Willcox
As the cars are aging I'm seeing more and more failures in the movements of the tachometers. While the board will probably solve your problem, there is a possibility the movement might be the issue.
I have left dash pad removal instructions on the web site should you decide to remove it.
Corvette Left Hand Dash Pad Removal Made Easy 1968-1977
Willcox
Last edited by Willcox Corvette; Jul 28, 2013 at 10:36 AM.
