I have a 92 Sierra which i have just converted to manual but now the engine won`t turn over. I believe the car thinks its in drive and not Park, hence not starting.

Does anyone know what wire i`m looking for and where it is??

Cheers, Ed.

 

When you removed the Auto box you would have disconnected the wiring connector from the "Starter Inhibitor Switch" this is what is closed when the box is in park or neutral hence allowing it to start. As you have removed this, you most likely have left the plug disconnected, you need to join these two wires from the now surplus plug.

Martin

 

You will have three wires going to the inhibit switch, one for park one for neutral, and the return, just find the switch, which on the auto's is usually on the selector itself, it will be immediately obvious which wires to join.
Are you using the original ecu ?, if you are, then you need to rewire slightly as unless it thinks it is NOT in neutral or park it will MAY not rev over 4000rpm, in which case just take a wire direct from the ignition switch to the solenoid terminal and wire the switch "open", or leave disconnected.
I assume it is the A4LD box that was fitted, I think the later ones had much more electronic control, in which case the above may occur, hopefully not of course, pretty sure if this is the case the loom/ecu connector is also different from auto to manual.
tabetha

 

OR just ignore all the above advice, find the inhibitor relay in the fusebox and join the two wires (one which is live when cranking and one which feeds the starter motor) with a bridge.