tachometer/speedometer
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Joined: Oct 2014
Posts: 83
Likes: 3
From: TN
tachometer/speedometer
1980 corvette - Speedometer is 15 miles faster than actual when driving, when engine is turned off the speedometer reads 15 mph. Kinda the same problem with the tachometer, when turned off the needle reads about 2000 rpm but when running seems to be recording properly. Not sure what to do! There is a, not sure what it is called, silver aluminum sheet that goes across the instrument panel that appears to have electrical contact for all the gauges. Could this be the problem?
Burning Brakes
Joined: May 2013
Posts: 789
Likes: 129
From: Los Banos CA
It sounds like you have two separate issues, as the tach is electrical, and the speedo is mechanical. But I don't think the circuit sheet behind the instrument panel would cause either issue.
What does the speedo do when the car is going from 0 to 15 mph? Does it go from 15 to 30 mph, or does it stay at 15 until the car hits 10-15 mph?
I wouldn't worry about the tach if it reads accurately with the engine running.
What does the speedo do when the car is going from 0 to 15 mph? Does it go from 15 to 30 mph, or does it stay at 15 until the car hits 10-15 mph?
I wouldn't worry about the tach if it reads accurately with the engine running.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,851
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
We have a video on how to remove the needle and re-set it on the speedo... it's around the 12 min. mark in the video if you want to skip ahead
In regards to the tachometer, the original boards were designed to remember the last known input RPM's so it's common for the needle to be around 700-1000 rpm's give or take. When we did our tach boards years ago this was one thing the imported boards and other boards on the market place didn't do and so we incorporated this into our board so it would act and function just like the original boards. But..... For you, if the tach is working properly though for you, if it ain't broke don't fix it.
Ernie
In regards to the tachometer, the original boards were designed to remember the last known input RPM's so it's common for the needle to be around 700-1000 rpm's give or take. When we did our tach boards years ago this was one thing the imported boards and other boards on the market place didn't do and so we incorporated this into our board so it would act and function just like the original boards. But..... For you, if the tach is working properly though for you, if it ain't broke don't fix it.
Ernie
