C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Tach problems

Thread Tools
 
Search this Thread
 
Old 09-30-2002, 05:42 PM
  #1  
bobt007
1st Gear
Thread Starter
 
bobt007's Avatar
 
Member Since: Sep 2002
Location: London Ontario
Posts: 1
Likes: 0
Received 0 Likes on 0 Posts
Default Tach problems

The Tach is running 1000 to 1500 rpms below actual rpms on a 1981.
Any ideas why?
Old 09-30-2002, 08:48 PM
  #2  
Geoff1340
Instructor
 
Geoff1340's Avatar
 
Member Since: Sep 2001
Location: Jacksonville Fl
Posts: 122
Likes: 0
Received 0 Likes on 0 Posts
Default Re: Tach problems (bobt007)

I'll trade you...mine reads 1000 or so RPM high. Don't know the fix either... :confused:
Old 09-30-2002, 11:34 PM
  #3  
SanDiegoPaul
Race Director
Support Corvetteforum!
 
SanDiegoPaul's Avatar
 
Member Since: Sep 2002
Location: San Diego - Deep Within The State of CONFUSION!
Posts: 10,362
Likes: 0
Received 2 Likes on 2 Posts
Default Re: Tach problems (bobt007)

Trade BOTH of ya! My '76 just stares at me when the tach should move.
Old 10-01-2002, 12:29 AM
  #4  
HawkIVette
Melting Slicks
Support Corvetteforum!
 
HawkIVette's Avatar
 
Member Since: Mar 2000
Location: Northwest Iowa
Posts: 2,975
Likes: 0
Received 1 Like on 1 Post

Default Re: Tach problems (bobt007)

Don't know if this will help you or not, but here goes.

When I had to replace my circuit board on my 75 ( keep in mind, 75 is when the vette went to electronic tach, though I don't know if was still electronic on the 81), there were instructions on "zero"ing in the tach needle after replacement of the board.

I think it went something like this.
With the key in the off position, your tach may read between 0 and 100 RPM. Turn the key to the on postion with out starting the car and the needle should go to "0". If it doesn't, you have to carefully pull the needle off the dial and replace it to point at zero. As I said, the key must be in the on position with the car not running.

Did this just start reading off, or has it always read on the low side? Your car may just have a curcuit board going bad.

Get notified of new replies

To Tach problems




Quick Reply: Tach problems



All times are GMT -4. The time now is 09:46 PM.