The tachometer on my 1991 C4 reads double the actual RPM. Is there a filter in the wiring harness or tachometer head that filters the input signal. If it is located in the harness, were is the specific location and what am I looking for. Thanks for any help.

 

None that I know of. Tach gets it signal directly off ground side of ignition coil, it actually measures the rate at which the ignition module grounds coil. More than likely, you have tach problems. [:@]

 

Thanks LB for the response. The tachometer issue that I origanal requested information on must not be a significant problem based on no other responses. It looks like the tach is coming out.

Thanks again
Brandy