Hey bro sorry to bump this up, but did you ever figure this out?
This is exactly my problem
i also think i have a blacktop harness..but i have a redtop engine 62
-I installed a skinny o2 like im suppose to but the harness might be wired different
Harness ............... 02 sensor
brown wire-----------Red wire
white wire----------black wire
black wire----------white wire.
i Think since it might be a blacktop harness; the black and white wires are reversed...so i might have to
re-pin the o2 to match. that's if its wired wrong..
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