The B-12 in the pourable long-neck bottle or the one in the stubby container labeled for use in the gas tank and the crankcase (for a flush before an oil change)? A scan of the constituents revealed the latter to be more toxic
, with a significantly different list of ingredients. I've used the pourable fuel-system cleaner many times too, but now use Techron at every oil change.
If the B-12 did dislodge / breakup the crud as theorized here, I expect some of it to have gotten dissolved in the various solvents., esp after 3 back-to-back treatments.
At any rate, it seems foolish to spend $100 and cut up your 'tour before you spend $6 to try this fix. I'm stall-free for 2k miles and loving it..
