Okay, so I'm pretty sure there's no dedicated thread about this yet, but I've seen it discussed in several other places. Today, I went through ECU pinouts for both '88-91 and '91-93 to make sure that now that I have swapped the 1993 Cobra computer into my 1990 automatic harness, there aren't any conflicts there. I found the pinouts here. http://www.veryuseful.com/mustang/tech/engine/
Anyway, I even made a spreadsheet comparing the two. The wire colors changed a lot, but the functions seem to all be the same.
Next we come to the O2 sensor harness question. I've found elsewhere here that you need to move the jumper wire on your O2 sensor harness from one circuit to another when you swap from automatic to manual. This hadn't been an issue for me before now since I had been using the A9P automatic computer. But now that I have the Cobra computer, it needs to be addressed. Mine seems to be the same as this
The jumper is currently going to the White/Purple circuit which.... I don't know what that does, but it's where you put it for an auto. So I guess I need to move it to the Light Blue/Yellow circuit which is the connection between the neutral safety switch/clutch pedal switch circuit and the ECU (I think, given all the wire color changes). I can't imagine what that has to do with the O2 sensors, or how it connected to the ECU before now without that jumpered, but... whatever, I guess. Anyone know?
I do notice though that both the NSS and the clutch pedal switch are looking for the switch to be CLOSED when the car is in neutral or the clutch is in so that the engine can be started. I'm guessing the programming for what to do with that information must just be in the ECU itself.
Any input? Am I on the right track? Thanks!
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