RPM Rising to 3K after Installing New O2 Sensors!!! Please Help

[MaRu_GT]

What I was trying to say was that even though your loop wire indicates its setup up for a Auto Trans, that the Circuit on the opposite side may not be the NDS and Auto circuits, It may be connecting Manual and Auto which is probably what it is doing.

There is a few other things it could be, but this has to be fixed first regardless.

OK the loop was re-pinned to the first pins on left top and bottom (in the pic MANUAL & NDS) , and now the car idles with no high rpms, it's back to normal

Thanks in millions buddy, I hope that old set-up didn't affect the computer.

There is only one observation, if I press more on gas padal and at rpm like 3k-4k, the car would give black smoke and you hear a ping from the exhaust (like back-fire ) ... I set my timing on 10 deg with spout disconnected - which Iguess is around 18-20 deg with spout connected. Also, the FP is set on 38-39 psi with vacuum line disconnected.

In fact, I am going to write a custom tune using TwEECer RT. That's why I put my timing and FP on stock. I just wanted to understand why this smoke and ping.

 

[jrichker]

Go back and try to dump the codes. If they don't dump or don't come up with an 11, you still have computer/wiring problems.

 

[MaRu_GT]

So I found this thread which I think it's very useful,
Oxygen sensor Harnesses - Manual/Auto differences and year differences - Ford Mustang Forums : Corral.net Mustang Forum

After the wires swap i did, mine looks exactly like pic#4 (90 manual pic) and now no issues. It used to be like pic#3 (for 91)