Here is an old thread i created a few years back when i needed to fix mine. Keep in mind i have a v6, but should be the same for a v8.

http://camaroforums.com/forum/82-92-...-raitos-70327/

Aight last night August 19, 2012 i took the board out of the cluster that controls the Tach Gauge, there is a lil black and white resistor chip on the board. I followed a thread on another forum and measured my resistance.

My resistance between pins 4 and 10 was 299-300. The actual resistance should be around 200 give or take,. I purchased a Actron Multimeter that reads engine RPMs and pluged up the RED lead to the DIST and the BLACK lead to the body. I also purchased a potentiometer 1meg ohm. Soldered to pins 4 and 10 on the chip, then matched the resistance that the tach needed to match as close to the Actron device as possible. 200rpm on the actron is 2,000rpm.

In all i have learned that sometimes whats wrong with the car is just a loose nut behind the wheel that can't leave anything alone lol. here are some pictures maybe this will help others out.