I've searched the sight the web and talked with MSD and Autometer to no avail. I swapped a 2011 gt500 engine and stock pcm into my 1986 notch, build the harness and it runs fine, tuned and almost everything works. I can not figure out how to get the tach to work. I tried an MSD DIS tach adapter it didn't do anything( I assume its good no one knows how to test them) tried the #25 pin on center plug of pcm thats posted for the 08/09 shelbys and that didn't work. does anyone know for sure how to make the stock 86 tach work with this engine/pcm?
OK UPDATE ----------------
PIN 25 does nothing on my pcm. not sure if that was earlier pcms or what. I hooked up MSD DIS tach adapter to neg side of coil and factory tach works at idle and upto 3000 rpms. once at 3000 it drops to zero until engine rpms fall back. any ideas? I, hooked off passenger side coil pack harness.
OK UPDATE ----------------
PIN 25 does nothing on my pcm. not sure if that was earlier pcms or what. I hooked up MSD DIS tach adapter to neg side of coil and factory tach works at idle and upto 3000 rpms. once at 3000 it drops to zero until engine rpms fall back. any ideas? I, hooked off passenger side coil pack harness.
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