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When I rebuilt that old slave cylinder, I included an internal spring. So now I have both internal and external. It gives me guilty pleasure thinking that the two of them are battling it out on my car right now! Hahaha!! 😄

Sorry for geeking out. I was on a roll. 😄

I found an old thread with several of us iin it. I feel kind of dickish reading my old comments. Hopefully I've mellowed. The 6801 has come up before, I'd forgotten about it. I also pulled up the 79 and 83 EFI ECU wiring diagrams and they seem essentially the same. Odd though that the 79 diagram doesn't show the O2 sensor circuit to the ECU. Just interesting that they apparently added the microprocessor to what had been a processor-free system. 1979 Uploading Attachment... 1983 Uploading Attachment...

Thanks much guys. That certainly explains why there isn’t an internal spring. I kept seeing the later version, and was pretty sure I didn’t loose it.

Your analysis of the parts is correct... Resistor, zener, capacitor - Those three parts are used for power supply and regulation*. They are relatively easy to source, and other than the zener voltage, the specs are relatively unimportant. By that, I mean... You could use a 180 Ohm resistor or a 150uF cap. Within reason, the values don't matter. The resistor will dissipate less than half a watt, so a one watt resistor would be fine. Composition (wirewound, metal film, carbon... Doesn't matter.) Crystal, and control chip - Those two are not easy to source. Hope that your problem is not one of those two. The HD44001 control chip does not appear to be available. Probably designed for the application and sold only to the clock manufacturer. And I would try hard to not mess with the crystal. The frequency is a little unusual, and even if you can find another crystal with "close enough" frequency, it's not guaranteed that it would work paired with the electronics inside the control chip. They are used as a shunt regulator system with the cap as a filter. System has about 30 mA quiescent current and therefor a little less than that in compliance.