280z AFM lead?

[Dave WM]

while I have been looking over what seems to be some non OE wiring around the dizzy term block I came across this pic in the FSM. I see the lead coming from under the AFM a single wire that looks like a locking spade connector. I think the PO replace this with a ground wire (has eyelets one side bolts to the bottom of the AFM the other side to the chassis ground thru a mounting bolt that secures the AFM mount to the chassis). Can someone confirm this is what this wire does? I could not find anything from the wire harness that looks like the pic at the top of the page.

AFM lead.pdf

[Zed Head]

That might be one of those FSM errors.  I think that all AFMs use the round eyelet as a ground.  I've seen a lot of AFMs and never seen a wire with a connector coming through the hole in the AFM base like that picture shows.

[SoCalJim]

Dave, my ‘75Z (California Model) has a single ground wire with an eye connector.

 

[Dave WM]

ok that looks like mine, only diff is the extra ground wire from the green wire on the term block that mine has.

A guess here, the AFM is electrically isolated from the chassis due to the use of the rubber gromments used to mount the plate to the chassis (I presume to damp vibrations). So with all that air flowing thru the alum body of the AFM it could build up a static electrical charge with out the ground lead.

So that lead makes since but my grounding of the diff green wire does not. My play is to get one of the HEI modules as ZH has mentioned just as a backup, will wire it up and just control the coil by choosing which module is hooked up. I read some comments by ZH in another thread where he just left the OE stuff in place and would just disconnect the signal at the OE module and then hook this one up under the hood.

All this is really just so I don't get stranded on one of my long road trips, so a tested backup system would be nice to have.

oh btw my test stand engine does NOT have the AFM grounded, something I will take care of since I don't want to smoke an ECU.

Edited December 28, 2019 by Dave WM

[Dave WM]

here is a pic of my setup

 

[EuroDat]

I think that spade connector is a legarcy from the early Bosch system they used in the first 280Z's

I have seen it on an Alfa over here.

[zclocks]

Dave, 

I have a very early 75(1/75) and it looks like the FSM, at least the connector ground. No additional wire (green) coming from the terminal 

block. My green wires go into the harness! 

Ron

[Dave WM]

well I went out today and tried it again, this time with extra ground (the non OE looking one that goes into the term block green lead) disconnected, and it started right up. Not sure why that was not the case before, but presume it was something else before causing the no start. Anyway I am going to keep that disconnected for now and get some drive time in!

[zclocks]

Dave, 

A couple more photos of what My 75  looks like. No Ground wire attached to the terminal block. Mine is bone stock

Ron

[SoCalJim]

Mine looks just like Ron’s.  Well, except for the Green Metallic paint instead of red. ? 

[Dave WM]

I don't recall that large spade connector coming off the harness of mine (looks purple in the pic). I did remove the non OE ground, so far it works fine. The non OE ground may have been causing some issues, as I went to remove it, the poor crimp on the eyelet just let go. Could have been an issue if vibration setup causing spurious signals.

[Dave WM]

I just checked my harness no sign of that purple lead with the large white locking spade connector. The harness looks complete with no signs of hacking. If you look at my 1st pic you can see it is missing. Wonder what that is for?