[Gmecm] 4 out buffer and 7747

[Brandon Austin]

I have been off list for a long time but searched/read much of the archive
first.

I am using a 7747 to run the TBI on my '87 Toyota Land Cruiser.  I am trying
to use the VSS in my speedo for the signal to the ECM but it is a 4 pulse.
I tried to wire in the "4 out buffer" from a '88 Trans Am.  I know I have
good signal in as I have tested the 4 pulse into the ECM.  I connected the
Red/black to ign pos, the black/white to ground, the brown (2kppm?) out to
the ECM.  For the VSS in, I have tried both the yellow to signal and purple
to ground and the other way around.  The VSS only has signal out and is
internally grounded.

I have also read that the buffer takes in a mag signal and puts out only
digital.  Can the 7747 receive a digital VSS signal?  Do I just need to go
back to the cable mounted VSS (the last one broke apart after 6 years)?

Brandon