1227747 DFCO not working; one more question

[JF in MI]

I think I'm seeing the issue but have another question. I installed a Painless Performance #60116 speedometer cable VSS which is advertised to work with TBI computers. My raw data was showing function but on second examination I'm not registering speed all the time. In fact (running the car on the lift) most of the time it doesn't show speed under about 60mph. Above that it's good (albeit showing way too high speed) below it stops reading and goes to zero. I took an AC voltage reading off it and am showing around .4 volts to 1.9 volts at higher speeds. I'm wondering if it simply is not putting out enough voltage for the computer to read. Does anyone know what kind of typical voltage should be seen for this number ECM? Also any recommendations for a cable VSS that has worked with this ECM?
Does all this mean nothing and do I just need a DRAC?

[stew86MCSS396]

I think you want the #60115 2k pulse VSS that the '7747 is looking for. I am uncertain as to what input signal the DRAC requires, thinking it is used with a 40 tooth reluctor which generates way more than 4k pulse per mile.

[JF in MI]

I think you want the #60115 2k pulse VSS that the '7747 is looking for. I am uncertain as to what input signal the DRAC requires, thinking it is used with a 40 tooth reluctor which generates way more than 4k pulse per mile.

Thanks for your reply. I've been fooling with it some more and the MPH readout, when I can get it, is all over the place. It comes in now at around 35MPH (by the mechanical speedometer) and reads around 14 MPH then goes way high (over 100) at over 60 (by the mechanical speedo). I'm thinking that the ECM simply does not like an un-buffered signal.