Car management has to re-learn? I didn't know they were that sophisticated in 1990. I will check my WIS under CPS testing. The tach works perfectly. With an ohmmeter, am I just checking for contuinity on each wire looking for breaks?

I am not sure I understand your question about a CPS code on the 8 module. If you are referring to pin 8, I only have readouts on pins 3,6,7 & 14. Except for the push button and LED, all other pins are blank.