You might want to try it again. I think that a repeat performance may get the harder stuff out.

It would probably be more effective to use a pint/quart of water to remove carbon deposits...introduced slowly AFTER the MAF using an old dish soap bottle.

Then using some Seafoam in the plug openings and left to soak on the rings overnite. Turn over with no plugs...then replace them.

Then change the oil and filter.