Does anyone know somebody that can help me here ? I need my Factory '96 Sunfire Tach to work using an aftermarket Tach to drive it.

I took a Super Pro Tach that I’ve been using in my Sunfire, and pulled it apart. I kept the control board and connections. I pulled the Instrument Cluster out of the Sunfire and severed the connections to the Stepper Motor in the Tach Face. Using what “I” thought was logic, I connected the Super Pro Tach control board to the Stepper Motor in the Sunfire Tach. Thinking that pin orientation is critical here, I played with the radial orientation until I got a response. It’s either “0” or “5,000” or “Pegged Out”. At least I do get gradual movement from”4,000” to “5,000” in one configuration.

I don’t know what to look for on the SP control board or how to tell what the Sunfire Stepper Motor wants.

The Sunfire Stepper Motor has labels for the pins on the back. Orientation stated here is looking at the Tach face from the drivers seat.

Sin+ at 8:00
Sin- at 2:00
Cos- at 5:00
Cos+ at 10:00

Any ideas ??? Thanks...

After all of this, I have decided to get another aftermarket Tach and use everything but the face to get the Factory Tach to look like it works. Anyone know of a Tach that moves 90-100 deg's between 0 - 6,000 RPM's ?