In the process of converting from tbi to tpi I ran into a slight wiring delema with the speedo and the cruse control.

The main reason that I am writing this is incase others are having problems.

First off the TBI uses a VSS Buffer the TPI does not it is in the ECM. So two connections from the removed VSS buffer harness have to be spliced into the Clear connector ((C207) in the Helms manual) on the ECM TPI harness.

You no longer need the VSS Buffer from the TBI after the swap, do ditch it. On the harness there is a wire at pin C (tan)you need to clip it and attach an extension wire and run it to pin D (grey wire)on the new clear TPI connector. This will allow your speedo to work. (Of course if it is a electric speedo)

Second, to get the cruse to work. On the VSS Buffer harness find pin E (red wire) clip and extend a wire to pin P on the new clear TPI connector.

That is it now both your cruse and electric speedo should work.

Hopefully this will save some of you time on your swap.

 

Thanx alot for the great info and takin the time to post it ill need it

 

Has anyone else done this? I looked on my TBI Buffer box harness and I didnt see those same color wires in those positions (I forget which colors they are now...)

 

I have no grey wire at the clear connecter its blank