So I picked up a Buelltooth and have been poking around in the ECM. I see the AFV is WAY down at 85.9%. I tried to reset to 100% and go for a good ride. Afterwards, it was again back at 90%. I replaced the spark plugs with NGK Iridiums (DCPR8EIX). The plugs I took out were OEM and black tipped (see pic)

It seems to bog quite badly especially at low speeds. I'd like to resolve the issue and I done some reading on here that intake seals and/or an 02 sensor could be the issue? For reference it's an 08 Anniversary Edition with 18,600 miles (30,000 kms)

Any advice from the resident experts?

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