At one time Mr. Cahill said that you could actuall hook up an aftermarket tach (in a second gen) without the use of a tach adaptor but tapping into pin B11 which is a white wire because that is the signal wire on cars with an ECM with 3 plugs. I believe him, but my 1993 and my old 1992 have a 2 plug ECM and pin B11 is like orange with a stripe or something (not white).

Which one is the tach signal for a 2 plug ECM?



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Tomorrow I will get a pic of my tach wiring if you want...

I was told that on Sunbirds you can wire it from the coil but if you do it from the ignition module on a Cavalier you will only get half the rpms.


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