Bad misfires on cylinder 6 (P0306 & P0131 o2 sensor low voltage b1 s1)

2012 FORD F-150
197,000 MILES • 3.5L • TURBO • AUTOMATIC
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REGGINA
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  • 8 POSTS
Driving home from work last night I started to misfire on cylinder 6. I swapped a good coil and put a new plug in, still the same. Its a very bad misfire under very little load, have to slowly accelerate. Truck shakes, however the misfires aren't as bad at lower speeds (0-40). I recorded some live data and when I try to apply gas my absolute load value will go over 100% under normal operation.

I have noticed a rougher idle at start up over the last few months and a slight tick
Sep 24, 2026 at 2:30 PM
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REGGINA
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  • 8 POSTS
I assume I should check compression?
Sep 24, 2026 at 2:55 PM
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