Stock my 87 GTA had 1 orange wire going to ECU that had a park neutral signal>>> what did this do??? If I leave it disconnected will it cause any problems???

 

It let the ECM know when the trans was placed into drive. The ECM could then compensate for the additional load.

The signal was grounded for in park/neutral, open for drive. Stick cars just left the wire open.

RBob.

 

yup.


so if you have a auto car that you converted to a manual, and you keep stalling as you're coming to a stop, you just disconnect that wire from ground, and it always thinks you're in gear.

then you can drive it without a new chip..

 

I hate to open a old thread but I wanted to be sure on this:

The ecm needs a negative signal when the car is in park or neutral? As long as it sees a "ground" in park or neutral and nothing in drive or reverse it'll work fine?

Thanks!

 

Yes, just leave the wire open, not connected to anything, for 'drive'. With an automatic that wire is grounded when the shifter is in park or Neutral.

RBob.