Magnum Swap, which 02 sensor to use, pre-cat or post-cat

Never seen this happen on these engines

When I was first getting my EFI set-up running, the car would go into limp mode when it transitioned from open loop to closed loop after the first minute of running.

It turned out that I had an open ground circuit on my O2 sensor. A quick bit of solder, wrap of tape and some heat shrink solved the issue. The Matco Scan tool I had borrowed from a buddy allowed me to find the issue. Without a good scanner, it would have been nearly impossible for me to diagnose. You can see where I had to ground the wire in this picture.

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